Review of my [troublesome] experience with Samsung Galaxy i9505 S4 (WARN: LOTS OF TECH TALK)

[KD007]

Before I start, I would like to inform the reader that I am using an unlocked T-Mobile Samsung Galaxy i9505 S4 (jftetmo) on a Canadian network called Fido with custom roms (lol, uber-hacked).

First off, I would like to address a problem with Galaxy S4's in general, namely the hardware. Many end users don't know this but when you're dealing with Samsung, the S[insert number here] nomenclature of the models is [b]completely irrelevant[/b]. Depending on your carrier and country, the Galaxy S4 that you purchase may be COMPLETELY different from another S4. Even the CHIPSET! Since I am using the North American version, the hardware inside (chipset) is a Qualcomm Snapdragon. Other regional models such as China and international have (debatably) a more powerful and newer chipset called Exynos. [b]This means that Samsung is selling COMPLETELY DIFFERENT AND CROSS-INCOMPATIBLE PHONES under the same name; in the same cases (apart from the model/carrier inscription).[/b] Another general S4 hardware issue is the amount of manufacturer mistakes that have been going on since the launch. There are two really famous ones:

The first problem was the battery overheating/bloating/igniting(!)/exploding(!). This affected mostly EU versions, especially the Exynos ones. My phone does not have this issue.

The second problem was with the early models having a faulty modem. This affects me largely to this very day. As some of you may know, people install custom ROMs on their android phones to add root access, remove annoying manufacturer/carrier crap, and to add various things that help developers. The issue arises when a person has a zero-day (US OR INTERNATIONAL) Galaxy S4 with 4.2 or 4.1 and upgrades to 4.3. What happens is when the phone is on LTE mode, locking and unlocking the screen causes all mobile data and network coverage to disconnect until one turns airplane mode on, and off shortly after. This meant that I had to get my hands dirty and install an MK2 modem firmware through odin (bleh). Although the reception is more responsive now, I still see that problem lurking around the corner. I was really scared when doing this because it was rumored that installing an Mk2 modem can break all sound functionality (fuck yeah, more problems!). Luckily, this wasn't the case...

In terms of the software/firmware, I really like the TouchwizUI that Samsung has to offer, but it is a real pain when it comes to modding/skinning it. There is a module called WanamXposed that lets you partially do so, but it consists of a lot of dirty hacks from the looks of it.

All in all, the Galaxy S4 is a domino effect of problems. Unless you want to stay on the shovelware-bloated, non-rooted, unmoddable Samsung rom, you will need to install another rom (preferably a modded Samsung one) and bravely face the platoon of issues that is headed your way. [i]One ROM fixes that, but breaks this[/i] is the name of the game with this model.

By the way, the issues I have listed (even the modem one) have been happening even to people on locked, stocked and default firmwares. So don't try to negate my whole post with the words "it's cause you hacked ur phone". I spend a lot of time reading XDA dev stuff regarding android development (mostly Samsung-based).

[QUOTE]
[b]Review conclusion[/b]
[b]Functionality: [/b] very functional, lots of features, especially with custom ROMs
[b]Stock ROM stability: [/b] Generally stable with some potential issues (due to Samsung)
[b]Custom ROM stability: [/b] Even less so stable
[/QUOTE]

If anyone is keen to know which ROMs break the mobile data, I have only tried two that have caused the issue: WickedRom 9.1 (4.3-based) and HyperDrive ROM (also 4.3-based). Mine and a lot of people on xda's guess is that it happens with any custom 4.3-based ROM, really. Again, flashing the Modem to MK2 seems to help enough. After the flash, you will still see the signal disappear after lock, but luckily, it comes back right when you unlock or wait for a few seconds on the lock screen. The reason why I am so hung on this issue and its solution is because if you read the forums, you will literally see hundreds of users asking why this is happening. Few of them already know the answer. This is quite sad..

[KD007]

Is the Qualcomm really faster than the Exynos? Didn't they bench differently depending on the kind of task? I would imagine the Exynos to be more affine since it is a hex core.
Not to mention the fact that even two Qualcomm-based S4 models can end up with different clock speed tunings, again depending on the carrier. Some some carriers give out Snapdragon models clocked to 1.9GHz. Mine is clocked to 1.6GHz. Ofc, I won't complain about this, since you can tweak all that crap out through the kernel. KTweaker is buggy but really simple to do all of that nice stuff in.

Also, network related, the tethering doesn't always work on all roms (even ones meant for SGS4 i9505) unless you do some init.d tweaking and set up some script that writes manual VPN settings. I believe it doesn't always route out to the network by default. This affects me very well on the current ROM. I'm still too lazy to fix it :/.

[Gammashack]

Also, any s4 with the 4.2.2 (ME7 I think) OEM or after gets the boot loader locked. The only way around this is using safestrap, but that gets annoying only having 16gb.