Samsung Galaxy S4 Forum

General Internal vs SD Memory

The Galaxy S4 is going to come with 16/32/64 gb of internal memory, plus some sort of a SD card slot. I am sure that SD cards from Newegg will be cheaper than whatever is changed for more internal memory. Is there any reason NOT to buy the 16 gb model when it is available and then add a large SD card? I will never use more than 80 gb of storage (yea, i know, famous last words...).


#1 stevendm, Mar 18, 2013
I realize that the S4 is not out yet but how is memory handled in stock android? Is there a performance difference between internal and SD memory?
#2 stevendm, Mar 18, 2013
Welcome to the forums! :)

I'm glad you've raised this issue, I think you've voiced a common question.

Android is all about choice, and Samsung has upheld that ideal that ideal to the highest standards where the SGS4 is concerned with storage choices (and no, I don't work for them lol).

First - a note about on-board storage - it's technically called flash memory, and it's the same exact technology as USB sticks that you may use for your PC, just like what you'll find in a separate sd card.

The built-in storage on your Samsung will always be superior to any sd card. Samsung leads the industry in mobile memory-storage chips - just as a point of reference, my last two HTC phones used Samsung storage chips - they're simply the best. They're the fastest and most advanced.

So, if you absolutely must have the highest-performing storage, you'll want to buy the model with it built-in.

When you buy an sd card it has a class rating - like class 6 or class 10 (the highest). That number is the certified rate, in megabytes/second (aka MBps) that the card will transfer data on writing.

Class 10 is way up there - 10 MBps. I use a 64 GB Sandisk class 10, and it's under-rated - instead of just 10 MBps, I get over 22 MBps download/transfer rates.

What do the numbers mean? The Blu-ray movie playback maximum is specified at 40 Mbps (note to HD fans, not talking disc here, talking movie rate) for full HD. In 2011, there were only 4 movies on the market at that rate. Most may have burst rates over 20 Mbps, but the vast majority of 1080p BD movies you may have average around 9 to 10 Mbps streaming rates. Divide by 8 to change Mbps to MBps and you get an HD max of 5 MBps.

So - if you absolutely must demand the highest-performance storage playback, you want a larger-storage SGS4 model. If it's a mixture, or you don't have those demands, going to a slightly slower class-6 card is for you.

Even though this is a 1080p phone - few will want to bother with the huge file sizes of Blu-ray movies on their phones. You can get perfectly acceptable performance by compressing those Blu-ray movies using a free solution like Handbrake, for example.

And if you're planning on just storing a boatload, the 64 GB model plus a 64 GB model is what you need.

If you do a lot of cloud stuff and don't use much storage - get the 16 GB model and forget about it.

If you want a good middle-of-the-road solution and aren't sure - get the 32 GB model, add an sd card later on.

I added a 64 GB sd card to my 2012 model phone because I had no choice - my only option (HTC model) was a 16 GB phone (not enough) and I didn't want to mess with storage, so I just went for the max. If you're like me on that, just get the 64 GB model and probably never worry.

I prefer using class 10 cards. I don't want to waste time writing to the card.

Those are my opinions on storage use - but the part about built-in memory by Samsung are facts though. ;)

Cheers! :)
#3 EarlyMon, Mar 19, 2013
Thank you EarlyMon for the very thorough explanation. I do very little in the way of movies, etc on my cell phone. Honestly, I am more worried about apps than video. Can apps be stored in internal as well as SD/external memory? I like to play around with apps and I think 16gb is plenty for even the most app crazy person around, but I just want to make sure that I buy the right toy ... oops, I mean phone.
#4 stevendm, Mar 19, 2013
I play 1080p from a $50 64gb micro sd and plays back perfectly. That said, I did for only tests, since can not tell a difference on a 10" tablet, yet alone a 5" phone if a 2GB 720p video or the same as a 10GB 1080p video. They both look just as great on a small display. I do notice the difference on my 27" LED monitor.

Added: For a portable device, 1080p seems a waste of space and battery power, but JMO.
#5 rushmore, Mar 19, 2013
EarlyMon, surely class 10 is 10 MB/s, and not 10 Mb/s (that is, MegaBytes, not Megabits)?

And I believe the ratings are for writing. For reading you're more likely to get 30-45 MB/s transfer rate.
#6 davoid, Mar 19, 2013

Good eye, correct on both counts. :)

Thanks for the catch!
#7 EarlyMon, Mar 19, 2013
So does this mean that a class 10 SD would be ample quick for a 1080p bluray movie?

As a rule of thumb I roughly equate Byterate to 1/10 the bitrate, so 40 Mbps bluray bitrate is roughly 4 MB/s so in theory even a class 6 card should be fast enough?
#8 davoid, Mar 19, 2013
Yep, I believe so.

Still the matter of getting the data to the card. I go with the fastest I can get.
#9 EarlyMon, Mar 19, 2013
Seems like apps want to be installed in the internal memory, not on the SD card.
Pictures, videos and music can be written to the SD card.
So the decisions would relate to how many apps do you want to have vs. media.
#10 Airstream25, Mar 19, 2013
As for micro sd cards and speeds, you may find this useful:

Class 2 for SD video recording
Class 4 and 6 for high-definition video (HD) to Full HD video recording,
Class 10 for Full HD video recording and consecutive recording of HD stills
UHS Speed Class 1 for real-time broadcasts and large HD video files
#11 XplosiV, Mar 19, 2013
While I tip my hat to EarlyMon's knowledge, I have found zero difference between a class 6 and class 10 card. Class 10 doesn't make anything fast while class 6 does nothing to slow anything down. Both cards can playback any HD video.

The real difference between a 16gb and 32gb device is how many apps you plan on installing and how large the apps are. Since ICS, there is no apps to SD, so all of your apps must fit on the 11.5gb of internal storage you will have access to. If you plan on going app crazy, then definitely get the larger storage. Someone might know if those 800mb Gameloft games install data on the external SD card or not -- I'm not sure which way they do it.

Otherwise, my SD card holds all of my music and photos/videos. And I am very glad I have that option.
#12 Cobravision, Mar 21, 2013
Yeah, I goofed that part, sorry.

Updated my post.
#13 EarlyMon, Mar 21, 2013
As noted previously, the read transfer speeds will be much higher so for playback a Class 6 is probably more than adequate. For recording Full HD video though, it may struggle to maintain a suitable write speed.

To further confuse the issue, the class rating specifies the minimum write transfer rate required, nothing more. It's not uncommon for a Class 6 card from a quality manufacturer to far exceed this; any Class 10 parts that fail testing will be most likely pass as Class 6 easily.
#14 Slug, Mar 21, 2013
Thank you Cobravision. That is the conclusion I have arrived at. I think I will go with the 32g, just in case. This information is very hard to find on the web because it it spread over so many sites, forums, etc. Thank you for the information in a concise form.
#15 stevendm, Mar 21, 2013
Unless you are making a daily backup, store anything of importance on the sd. I have tanked phones and the SD has been the only thing that made it.
#16 edge, Mar 21, 2013
This is an excellent thread. I actually learned something today! I honestly didn't know there wasn't App2SD support for the newer Android Operating systems. I'm still using my trusty old Evo 4G with Gingerbread and a custom ROM so I had no idea that it's no longer possible to move apps to sd storage anymore. I don't understand why they would do away with that feature. Good to know!
#17 djwebb81, Mar 22, 2013
Total storage (labeled rom) on the Evo was 1 GB - for the bootloader, radio firmware, Android and then a few hundred MB left over for your apps and data.

On the Evo 4G LTE with ICS, 1 GB alone is set aside just for Android - apps and data get another 2 GB. (And firmware and cache is in GB now as well.)

A2SD wasn't so much a feature as it was a solution for phones without much storage.

Moving forward to the latest generation - you'll never miss it, imo.
#18 EarlyMon, Mar 22, 2013
Wow I didn't know that either. Apps to sd is the only reason I'm not totally annoyed my S2 died, as I had moved almost everything to the SD a week or two beforehand (no it wasn't the cause), so I only lost a few (yet important) old versions of apps, which have a habit of being priceless. (for the ones I saved, I can install the new version, then paste the old com folder data over it via root)

I was already going to go 32gb this time but now perhaps 64 may be in order for me, as on top of not actually being able to access all 64, I feel I will need about 4-5 gigs of space to keep empty because my S2 (16GB) developed a long boot time between the end of S logo anim and home/lockscreen when it got near full.
However I am not keen on having to pay $200 more to get 48 extra gigs on the S4, bit of a scam that.

Also, waiting for media scanner to read the external sd card after booting is a nuisance, something for people to consider. Is there a class that would be read fastest?
#19 Gearu, Mar 23, 2013
I'm probably going to get the 32GB version of the phone since I have Galaxy Nexus now that has 32GBs of internal storage and to get anything less would be stupid. With all of my backups and whatnot, I still don't even come close to filling up the 32 GBs of storage in the phone.

I read somewhere that with recent changes to Android, there are no limitations in how the storage is used in the phone. All of the partitions (/system, /data, /sdcard, etc.) all pull from the central storage capacity as versus in the old days of Android where partition sizes were fixed sizes.
#20 trparky, Mar 23, 2013
The change to MTP allowed for the sharing of the phone's internal storage across all of the various partitions of the phone (/system, /data, /sdcard, etc.).

This is from an Android Developer at Google, so this is straight from the horse's mouth.
We didn't do this because we wanted to use ext3 (although that is a side benefit.) We did it because we wanted to be able to merge the "public shared storage" (i.e. for music and photos) with the internal private app storage.

We got tired of seeing OEMs include many GB of internal storage for music, while users were still running out of space for apps and data. This approach lets us merge everything on one volume, which is way better.
#21 trparky, Mar 23, 2013
Read speeds for SD card is theoretically the same -- the class applies to the write speed. You will not get any real difference in read speeds between a class 6 and class 10 card. The only reason I bought a class 10 card was to speed up the copying of 2gb-4gb files from my PC (mission accomplished).

If you have a phone that was released pre-ICS or released with ICS but has the same memory partitions as a pre-ICS phones, apps2SD still exists. For instance, you still retain the apps to SD functionality on a GS2 that was upgraded to ICS, but the "SD" memory is really internal storage. All you're doing is moving files from the app partition to the user storage partition.

In theory it's nicer to have one unified memory space in the phone. It's simpler for most users and you don't have to worry about where your files are going. But I take a TON of pictures and like having my music library with me at all times. Plus, I have a couple of gigs of podcasts downloaded at any given time. So 32gb wouldn't be near enough while 64gb is typically another $100 when I could simply recycle my older 32gb memory card (it's also extra onerous since I already spend extra money to secure a 1 year equipment contract with Sprint).

But getting rid of the app partition was the best move. I know the biggest problem with the older entry level Android phones was the tiny app partitions that didn't allow to to install more than a few apps and didn't have access to app2SD (which was a Froyo thing). My Evo 4G only had 512mb app space, but a third of that was for bloatware. Crappier phones had 100-200mb for apps, so they bogged down almost immediately after installing two or three apps.
#22 Cobravision, Mar 26, 2013
You can have the fastest card on earth, what is actually shocking is the speed of the USB interface of the phone.

I suggest, when moving a lot of data / big files to the external SD card, you use something like this - which really is a life (and mainly time) saver

(there are USB3 versions out there too)

You basically put the SD card into a USB stick and use that to transfer the data from your PC over.

Or better still, I run an FTP server on my PC and ftp files straight to the internal card - still a LOT quicker than the damn slow USB interface of the phone :)
#23 Gomjaba, Mar 26, 2013
I either use an SD card adapter like the one pictured or Solid Explorer to transfer files wirelessly. I have never used my phone in MHL mode. Actually, I don't think I've ever connected my Note 2 to my PC via USB.
#24 Cobravision, Mar 26, 2013
Edit: TRParky, I'm not whining at you. I saw that quote some time ago and it stuck with me. I'm whining at it. We're cool, hope it didn't seem otherwise.

The move to MTP has rather large inconveniences, at least due to Windows. I have a huge music library and like to keep large sections of it on the phone (never know what I'll be in the mood to listen to). Try copying MP3s to an MTP drive. You get warning what they may not work for EVERY FILE. Yes, you can answer once for that copy operation but the next group of MP3s will raise the same issue.

There also seems to be an annoying side effect where my stupid computer won't find all my stupid files/directories. It doesn't appear to be a permissions problem or even consistent. Some times one group of files will not appear, another time it's a different set.

I can't say whether all the driver hell I've been through is due to MTP or the lack of decent Samsung drivers. My GNex will NOT connect to my VMWare player running Win7, nor will my N7 (both MTP). My iPad works as does every flash drive I've ever tried. My home computers (native Win7) are slightly less irritating. Copying files off of the devices can be pretty dicey too.

Whining aside, give me removable memory so I can jam as much in there as will fit. I can also plug that memory into my computer and have it just work, without complaint. If I decide to wipe my phone, I can remove the SD card and KNOW it won't go along for the formatting ride like my Gnex did when when I installed Sourcery.

I'm not bitter. :)
#25 RichSz, Mar 26, 2013