[Xperia Z General] Supersaiyan.IV:
A few things had to be done since unboxing, and now I'm completely satisfied. Xperia Z is the best phone ever.

This is mostly experience speaking, but I'll link sources to motivate my reasoning. Also, all of below is revertible - therefore does not void the warranty. The few things I did so far:

Day 0 - Unboxing

If you received screen protectors with your Xperia Z I recommend installing them until you get better ones.

Baptise it in holy water. Root required.

Day 1 - Charge battery. Li-ion batteries like slow charging, slow draining.

Charged with phone completely off. [1]

Used a USB 2.0 (500mA) port to charge. Stock charger is 1500mA. [2]

Turned on phone once fully charged. Note: Try charging often enough to avoid deep 0% discharges and prolong battery life.

Here's Xperia Z's overall battery test score.

Day 2 - Get Adobe Flash Player working. Remove Google advertisements.

Install latest Adobe Flash.

Get Boat Browser. Then perform Settings -> Page Content Settings -> Enable flash/plug-ins -> "Always on".

Or Firefox, and perform Menu -> More -> Settings -> Plugins -> "Enabled".

Alternatively, download Dolphin Browser for Android and follow this guide. Root required.

AdAway, which was removed from Google Play market, removes most advertisements from Android. Due to Adaway's removal from Google Play it has moved to F-Droid market, which only houses ad-free and open-source applications. Root required.

Day 3 - Rooted Xperia Z

Discovered Towelroot and rooted the phone. To install application ensure: Settings ->Security -> "Allow installation of apps from unknown sources" -> Enable. Root acquired.

Updated the Superuser application directly after rooting. Superuser -> info -> "tap to check for updates" -> update. Root required.

Day 4 - Full-screen Navigation. No onscreen buttons. Phone/Phablet/Tablet mode. Change display resolution.

Try full!screen+ or GMD Auto Hide Soft Keys and see if they satisfy your full-screen navigation needs. If not, read below.

What we want to achieve.

Install Pie Control or the more advanced LMT Launcher, and setup it to your liking. Note how binding the standard menu and back buttons requires root.

As video description states, add "qemu.hw.mainkeys=1" to /system/build.prop using a file manager like Solid Explorer to remove standard navigation buttons and reboot. Root required.

To regain on-screen navigation remove "qemu.hw.mainkeys=1" from /system/build.prop.

Pixel density (DPI) can be changed with Texdroider DPI. Root required.

Phone/Phablet/Tablet mode changing is enabled by Phab7 module, which requires Xposed Framework to work. More modules are here. Each Xposed module can be regarded as a MOD. Xposed is a new safer framework for writing MODs. Root required.

Day 5 - Calibrate the Xperia Z display for better colours

Applied the display calibration utility from this thread and became a happier Xperia Z owner. Root required.

Downloaded the calibration utility and used Alternative Method to install it on the stock rom. If you happen to already have CWM use the flashable zip. Note: rw-r-r corresponds to this when using Solid Explorer.

Used the calibration values suggested in the first post.

Day 6 - 64GB microSDXC and exFAT

Bought a SanDisk Mobile Ultra microSDXC Class 10 UHS-I 64GB.[3]

Noticed phone formats the card to FAT32, which works just fine, but it limits file sizes to a max of 4GiB. If you're fine with max 4GiB files you can skip this entirely.

So I formatted the microSD card to exFAT on a computer, and installed [MOD] exFAT support for Xperia Z(non-Japanese verisons) to make the Xperia Z read exFAT filesystems. Root required.

Now the file size limit is 16EiB. Also, exFAT is optimized for flash memory unlike NTFS and HFS+ filesystems.

Day 7 - Useful Applications

Use Greenify to hibernate unused applications. Drastically improves battery time unlike application killers. If you want to use Greenify with Sony's STAMINA mode be sure to: Settings -> Power management -> STAMINA mode -> Add applications -> Pick Greenify. Now Stamina Mode and Greenify coexist. Root required.

User xperiax10.awesome has made a useful thread listing good applications that don't require root.

Outside of XDA there's androidpolice.com with weekly editions of Best New Android Apps and quarterly Top Android Apps Every Rooted User Should Know About.

Day 8 - Xperia Z Accessories

Detailed scientific reviews of expensive top-shelf headphones at Goldenears.net and HeadphoneInfo.com.

User DarkKrypt made an excellent thread on Sony Xperia Z Covers, Cases & Accessories.

Day 9 - Backup procedures and Sony Xperia™ Support phone repair. Read this before flashing MODs.

Because MODs might mess up your phone I'll review on some backup procedures and phone repair procedures.

The following will present steps to thoroughly backup Contacts, SMS and MMS messages, applications, and system settings. Photos and music included. Last two steps are repair related.

If you happen to have TWRP or CWM installed, do a backup from there. This will clone your present system in its entirety to a backup file. CWM or TWRP required.

Install Titanium Backup, Go Backup Pro or your favourite backup application.

If you settled for Titanium Backup do the following to backup, and this to restore backups. Titanium backup requires root, and costs a lot, but it is also the most powerful backup application out there.

If you used Go Backup Pro make a batch backup of everything important and follow instructions on the screen.

Save all folders containing backups, photos, music and anything of importance to your computer. Backups are in the folders named TitaniumBackup, GOBackup, clockworkmod and TWRP depending on the backup application you use. Photos are in a folder named DCIM. Copy everything if you're unsure.

If you messed up your phone Sony PC Companion can repair/restore your phone - here's a restore guide written by Sony Xperia™ Support. It will erase all data stored on your Xperia Z, so be sure to backup beforehand!

To restore your applications you might have to root the Xperia Z again. If you're only restoring Contacts, SMS, MMS, and Call Log there will be no need for root access. Restoring applications might require root. Copy all backups from the computer back to the device, then install the application you used to make the backups, and proceed to restore backups.

Day 10 - Custom Recovery. Flashing with CWM and TWRP on stock factory-locked bootloaders.

Install either ClockworkMod (CWM) or TeamWin Recovery Project (TWRP) to gain flashing capability. Note: CWM and TWRP can't read exFAT formatted microSD cards. This means if microSD is exFAT formatted you can only backup to phone storage. Root required. CWM or TWRP acquired.

Because the bootloader remains locked flashing will only work for MODs and STOCK based ROMs.[4] This means you can't flash AOSP[5], AOKP[6] and CM[7] based ROMs.

You can now also perform Nandroid backups. CWM or TWRP required.

Day 11 - Improving Xperia Z Audio Quality

Flash [SOUNDMOD] PureXAudio or [SOUNDMOD][Z/ZL/ZR][06/07][Pj.SNC] PureXAudio |442 Support to dramatically improve Xperia Z's MPQ8064 audio processing chip's sound quality. CWM or TWRP required.

Because the above MOD significantly increases audio volume I also chose to also flash the optional Stock audio volume patch. Be sure to not hurt your ears! CWM or TWRP required.

If you flashed stock volume, but want it loud again flash [SOUNDMOD] PureXAudio once more.

Day 12 - Considering Unlocking the Bootloader. Voids the warranty.

The advantage of voiding warranty by unlocking the bootloader is the ability to flashing ROMs requiring completely different kernels. Which means that an unlocked bootloader can disobey the information provided in footnote [4].

A disadvantage is the loss of DRM keys and BRAVIA 2 engine, however this can be prevented. Another disadvantage is that Sony PC Companion will not be able repair your phone anymore.

To prevent the loss of DRM keys and BRAVIA 2 engine perform the instructions provided in [Tutorial] Backup You TA Partition To Keep Your Drm Keys before unlocking. Be sure to read most of the 50+ pages of this thread, as performing the procedure erroneously may result in a bricked, non-functional Xperia Z.

Afterwards you may proceed to unlock the bootloader or simply skip this step and store the DRM keys for safekeeping.

Once the bootloader is unlocked most parts of this guide do not serve as a valid reference anymore.

[1] "It's best to turn the device off during charge; parasitic load can alter full-charge detection and overcharge battery or cause mini-cycles."

[2] ".. a battery wears down more quickly if discharged harshly and if force-charged with high currents.. "

[3] Xperia Z FAQ. Section 1: "Hardware Q&A"

[4] ".. kernel must be entirely stock including initrd otherwise its cryptographic signature will not validate.. "

[5] AOSP - Android Open Source Project

[6] AOKP - Android Open Kang Project

[7] CM - Cyanogenmod

Changelog:
2014-08-05
- Added Android 4.4.2 compatible PureXAudio MOD to section Improving Xperia Z Audio Quality.
- Modified link in section Day 2 as Dolphin Browser Beta is out of beta.
- Updated section Rooted Xperia Z with Geohots Sony Xperia Z (C6603) 10.5.A.0.230 compatible root exploit.

2014-03-12
- Added Xposed Framework, and Phab7 Xposed framework module. NOTE: Xposed Framework allows a new safer way to write mods. Every Xposed Framework module can be called a mod.
- Added a DPI changing application to Section Full-screen Navigation.

2013-07-23
- Added GMD Auto Hide Soft Keys in section Full-screen Navigation. Thank you [URL="http://xdaforums.com/showpost.php?p=43860706&postcount=72"]cimbomege[/URL] for the suggestion.
- Moved Adaway application to section Get Adobe Flash Player working.

2013-06-20
- Updated section Rooted Xperia Z with new exploit compatible with Xperia Z (C6603) 10.1.1.A.1.307.
- Added more disadvantages and remarks to section Considering Unlocking the Bootloader.

2013-05-17
- Updated section Backup procedures with more information.
- Added links to official TitaniumBackup backup procedure.

2013-05-16
- Edited a few section headings to make them comprehensive.
- Elaborated NFC remedy instruction in section Rooted Xperia Z.

2013-05-15
- Added section Considering Unlocking the Bootloader.

2013-04-24
- Added Greenify and Sony STAMINA mode coexistence instructions to section Useful Applications.

What else should be done to this Xperia Z?

Be sure to thank people in the posts I linked to above, thank you!