A Post about Removable Storage, Removable Batteries and Smartphones
by Anand Lal Shimpi & Brian Klug on November 25, 2013 8:40 PM EST- Posted in
- Smartphones
- Mobile
There's been a lot of talk lately about our position on removable storage and removable batteries in smartphones. Most of the discussion has centered around what we've said in podcasts or alluded to in reviews, so we figured it's a good time to have the complete discussion in one central location.
Let's get through the basics first:
All else being equal, removable storage and user replaceable batteries aren't inherently bad things. In fact, they can offer major benefits to end users.
The key phrase however is "all else being equal". This is where the tradeoff comes in. On the battery front, the tradeoff is very similar to what we saw happen in notebooks. The move away from removable batteries allows for better use of internal volume, which in turn increases the size of battery you can include at the same device size. There are potential build quality benefits here as well since the manufacturer doesn't need to deal with building a solid feeling removable door/back of some sort. That's not to say that unibody designs inherently feel better, it's just that they can be. The tradeoff for removable vs. integrated battery is one of battery capacity/battery life on a single charge. Would you rather have a longer lasting battery or a shorter one with the ability the swap out batteries? The bulk of the market seems to prefer the former, which is what we saw in notebooks as well (hence the transition away from removable batteries in notebooks). This isn't to say that some users don't prefer having a removable battery and are fine carrying multiple batteries, it's just that the trend has been away from that and a big part of the trend is set based on usage models observed by the manufacturers. Note that we also don't penalize manufacturers for choosing one way or another in our reviews.
The tradeoffs are simple with an internal battery, the OEM doesn't need to include a rigid support structure on the battery to prevent bending, and doesn't need to replicate complicated battery protection circuitry, and can play with alternative 3D structures (so called stacked batteries) for the battery and mainboard as well. Personally, I'd rather have something that lasts longer on a single charge and makes better use of internal volume as that offers the best form factor/battery life tradeoff (not to mention that I'm unlikely to carry a stack of charged batteries with me). It took a while for this to sink in, but Brian's recommendation to charge opportunistically finally clicked with me. I used to delay charging my smartphone battery until it dropped below a certain level and I absolutely needed to, but plugging in opportunistically is a change I've made lately that really makes a lot of sense to me now.
The argument against removable storage is a similar one. There's the question of where to put the microSD card slot, and if you stick it behind a removable door you do run into the same potential tradeoff vs. build quality and usable volume for things like an integrated battery. I suspect this is why it's so common to see microSD card slots used on devices that also have removable batteries - once you make the tradeoff, it makes sense to exploit it as much as possible.
There's more to discuss when it comes to microSD storage however. First there's the OS integration discussion. Google's official stance on this appears to be that multiple storage volumes that are user managed is confusing to the end user. It's important to note that this is an argument targeted at improving mainstream usage. Here Google (like Apple), is trying to avoid the whole C-drive vs. D-drive confusion that exists within the traditional PC market. In fact, if you pay attention, a lot of the decisions driving these new mobile platforms are motivated by a desire to correct "mistakes" or remove painpoints from the traditional PC user experience. There are of course software workarounds to combining multiple types of storage into a single volume, but you only have to look at the issues with SSD caching on the PC to see what doing so across performance boundaries can do to things. Apple and Google have all officially settled on a single storage device exposed as a single pool of storage, so anything above and beyond that requires 3rd party OEM intervention.
The physical impact as well as the lack of sanctioned OS support are what will keep microSD out of a lot of flagship devices.
In the Android space, OEMs use microSD card slots as a way to differentiate - which is one of the things that makes Android so popular globally, the ability to target across usage models. The NAND inside your smarpthone/tablet and in your microSD card is built similarly, however internal NAND should be higher endurance/more reliable as any unexpected failures here will cause a device RMA, whereas microSD card failure is a much smaller exchange. The key word here is should, as I'm sure there are tradeoffs/cost optimizations made on this front as well.
The performance discussion also can't be ignored. Remember that a single NAND die isn't particularly fast, it's the parallel access of multiple NAND die that gives us good performance. Here you're just going to be space limited in a microSD card. Internal NAND should also be better optimized for random IO performance (that should word again), although we've definitely seen a broad spectrum of implementation in Android smartphones (thankfully it is getting better). The best SoC vendors will actually integrate proper SSD/NAND controllers into their SoCs, which can provide a huge performance/endurance advantage over any external controller. Remember the early days of SSDs on the PC? The controllers that get stuffed into microSD cards, USB sticks, etc... are going to be even worse. If you're relying on microSD cards for storage, try to keep accesses to large block sequentials. Avoid filling the drive with small files and you should be ok.
I fully accept that large file, slow access storage can work on microSD cards. Things like movies or music that are streamed at a constant, and relatively low datarate are about the only things you'll want to stick on these devices (again presuming you have good backups elsewhere).
I feel like a lot of the demand for microSD support stems from the fact that internal storage capacity was viewed as a way to cost optimize the platform as well as drive margins up on upgrades. Until recently, IO performance measurement wasn't much of a thing in mobile. You'd see complaints about display, but OEMs are always looking for areas to save cost - if users aren't going to complain about the quality/size/speed of internal storage, why not sacrifice a bit there and placate by including a microSD card slot? Unfortunately the problem with that solution is the OEM is off the hook for providing the best internal storage option, and you end up with a device that just has mediocre storage across the board.
What we really need to see here are 32/64/128GB configurations, with a rational increase in price between steps. Remember high-end MLC NAND pricing is down below $0.80/GB, even if you assume a healthy margin for the OEM we're talking about ~$50 per 32GB upgrade for high-speed, high-endurance internal NAND. Sacrifice on margin a bit and the pricing can easily be $25 - $35 per 32GB upgrade.
Ultimately this is where the position comes from. MicroSD cards themselves represent a performance/endurance tradeoff, there is potentially a physical tradeoff (nerfing a unibody design, and once you go down that path you can also lose internal volume for battery use) and without Google's support we'll never see them used in flagship Nexus devices. There's nothing inherently wrong with the use of microSD as an external storage option, but by and large that ship has sailed. Manufacturers tend to make design decisions around what they believe will sell, and for many the requirement for removable storage just isn't high up on the list. Similar to our position on removable batteries, devices aren't penalized in our reviews for having/not-having a removable microSD card slot.
Once you start looking at it through the lens of a manufacturer trying to balance build quality, internal volume optimization and the need for external storage, it becomes a simpler decision to ditch the slot. Particularly on mobile devices where some sort of a cloud connection is implied, leveraging the network for mass storage makes sense. This brings up a separate discussion about mobile network operators and usage based billing, but the solution there is operator revolution.
I'm personally more interested in seeing the price of internal storage decrease, and the performance increase. We stand to gain a lot more from advocating that manufacturers move to higher capacities at lower price points and to start taking random IO performance more seriously.
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NeBlackCat - Tuesday, November 26, 2013 - link
1) Every phone I've ever broken (usually involving water immersion or meeting a road at high speed) has still allowed me to pop the SD card out and recover data to set up the next one.2) My phone is critical equipment for my cycling. I don't want to be limited by the crap life of one battery or the need to bring along a generic USB charging battery (that must remain connected in order to work). I want to simply carry a spare, and pop it in if/when needed. This has saved my life before, when I got lost in the Australian bush and needed the phone's GPS for much longer than anticipated.
3) Phones have been thin enough for me for some time now. I don't care if the above require an extra couple of mm thickness.
Thus, I will never buy a phone without a removable data card (even if it's hidden within, eg. under the battery) or without a removable battery.
I hope the smartphone vendors don't cut off a significant part of their market by phasing them out, like the laptop vendors did by phasing out 16:10 high res (eg. 1920x1200) displays a few years ago. That would be equally idiotic. Which is sadly no guarantee of anything...
MikeLip - Tuesday, November 26, 2013 - link
I don't have any basic problem with fixed, internal storage. But you are speaking of THEORETICAL prices for it. The fact is that handset makers pretty much screw you over for internal storage, and some - like the Verizon Moto X - come with a miserable 16G and NO way to upgrade it. The argument I hear is hey, you have cloud storage! Or you can stream! But in these days of tiered data plans, streaming your music and video can get damned expensive very quickly. Maybe three or four years ago that argument would have been valid. It's not anymore. In fact, if you follow the money, I'm willing to bet that one reason removable storage has been eliminated is just to drive up the sales of larger data plans.I remember HTC saying something about not adding the SD card slot to the One based on space requirements. But the Asian version had one. So I'm not very confident that "no room" excuse is a valid one.
AbbyYen - Tuesday, November 26, 2013 - link
blah blah.. total BS!1st, Build in battery still need a hard shell else if when it burst, it will kill you straight! so more room theory is BS!
To prevent shaky battery, yes. You need build in. To total secure it at place.
main reason is so that you will change your phone every one and a half or two years.
2nd, expansion memory. It's always always not hard to find space for it in today phone where bigger is better. And to assign memory allocation are peanuts stuff...
Data (storage,transport etc) is the next century gold mines.. This is the thing that you are afraid to speak out. It is okay if you are in coverage where access of data are easy. The other thing is.. these thing is so small and phones are getting way too advance where sensitive data or codes can be access, transport and execute very easy. So that's why there are resistant coming in against it.
But mind you, not every corner of the earth are covered. You guys have been sitting or live warmly without thinking some of us that have to leave to go out there, set up factory, plunder resources, transporting them, fighting unknown war.. just so you can have a good life back home.
Be neutral, just say these stuff are useless because this is what you think, yours opinions. You are you alone, you can't represent the other people. Don't say that these things are useless cause the industry think so, the whole world user behavior decide so... who are you? the industry? the world? You know jacks about industry. just that you get some interview with those crooks and you understand the industry? those are eye candy, man.. In the very inner parts of them, they are trying to capitalize you in every ways and every single drops of you. egoism will kill you one day.
owan - Tuesday, November 26, 2013 - link
This article is a joke. "Nothing inherently wrong with user replaceable batteries and microSD slots"? Glad to see you're taking the consumer-first approach here. That whole stance is so backwards it hurts. Why are we sacrificing actual usability for apparently totally critical things like "feel" and "POTENTIAL build quality benefits"?What a complete and utter joke this site has become. Keep shilling for Apple and justifying their anti-consumer NAND pricing schemes and planned obsolescence. I'm done with this site
cboath - Tuesday, November 26, 2013 - link
Floppies would probably still be around if they held 4x more data than the average hard drive.It's a complete load of crap that companies sell the phone or tablet for whatever price and that price comes with 16GB of space. (12 of which you get to use on average). Then, if you need more It's another 100 bucks to get to 32GB, another 100 for 64GB and god knows what to get to 128.
Meanwhile, I can buy a 64GB card for a all of $29 (got an ad yesterday).
$200 to go to 64 internal (only adding 48) vs 30 bucks to add a full 64 externally. One side that is gouging big time. To me that's the benefit of the card right now. It puts more power (so to speak) in the consumer's hand by not forcing them to be gouged for storage space. I keep 20+ GB on my 32GB card. Not everyone wants to stash all their pictures and music on the cloud. Not everyone works where there's a great cell signal.
As noted in the article. The only way to get rid of the card is if manufacturer's do the unthinkable and not gouge people for storage space. Don't offer 16GB devices, start at 32 and make the price to the next level FAIR. No one wants to pay an extra $100 to add 16gb and go to a store or site and see 64gb sd cards for far less. It's offensive and drives home the gouged feeling.
markus_b - Tuesday, November 26, 2013 - link
You are right about the advantages of internal battery and flash. But today these advantages are largely theoretical. For example, if we compare the HTC one with the Samsung Galaxy S4: The HTC One has everything internal with a marvelous unibody design. But the battery is 2300mAh only vs 2600mAh on the SGS4. HTC did not take advantage of having more control over the design to add a bigger battery. On the SD-card side it is more of a price thing. I got a 32GB SGS4 with a 64GB SDcard inside. The upgrade from 16 to 32 GB was more expensive than the 64GB SDcard.As long as this remains the same I will firmly stay in the removable battery / SDcard camp.
In addition, all these phones are fragile enough (glass screen !) the I protect them with a case. In a case the advantage of a nice unibody design become irrelevant. What will change this is new, scatter proof screens, maybe the new bendable phones, as shown by LG, will get there.
Kaboose - Tuesday, November 26, 2013 - link
That's not really fair though, most people who get the Galaxy S3 or S4 are not hard core users. My little sister has an S3 cause it was free on contract, she doesn't even know the difference between internal storage and Sd card storage. Just because a product is popular does not mean it does everything right, or even what consumers would prefer. It just sells well because Samsung spends more than any other company on advertisementsMr Perfect - Tuesday, November 26, 2013 - link
Which also seems to indicate that casual users aren't necessarily asking for these features to disappear. Does your sister complain about the S3 having a flimsy back door? Or that the MicroSD card has a slower write speed then the internal flash? My guess is she honestly doesn't care as long as it's pulling in a decent 4G connection for Facebooking/Tweeting/InstaSocialWhatevering.If the casual users don't care one way or the other and the enthusiasts are upset about the features disappearing, the it sounds to me like you can make both camps happy by just leaving them in.
drumm_22 - Tuesday, November 26, 2013 - link
I think you may want to consider rewriting your post. Sounds like you are very one sided and overly biased. From the way it sounds, i would say you are getting paid by google or apple to help change peoples view on the topic.Impulses - Tuesday, November 26, 2013 - link
How does a card slot present any more of a structural body design issue than the SIM slots all phones already have?Don't get me wrong, I agree with most of the rationalizations and why the industry is headed where it is... Doesn't even particularly bother me as long as I can get 32GB+ for a reasonable price (got a N5 atm, first phone I've had without removable storage, second without removable battery).
If you were given the option between a N5 as is for $350 or a 16GB N5 with a card slot for $400 what would you choose tho? Most of the scenarios that require lots of storage are still ideally suited for removable storage, which gets cheaper all the time.
That's besides the point though, the real issue seems to be AT's treatment of the subject. Not penalizing or praising phones for going in either direction is fine IMO, it is what it is, people that need/want removable know which phones feature it.
There's still two things AT can do for it's readers though, cut the snark about microSD slots and actually praise/penalize phones based on internal storage. A company that charges $100 for a 16GB bump should get called out over it MUCH more.
Likewise, anyone that goes 32GB as base capacity should get some praise. If enough of those comments go around maybe we'll see some change.
Ultimately money and sales speak louder, but it shouldn't mean journalistic editorial comment concedes to every industry trend. Your opinions can change many others, and turn sales, and inflict change.