I have been tweaking my Nexus 4 since it was purchased from Google Play in the spring of 2013. I have poured over many articles from XDA, Qualcomm, Google, LGE, and a host of others. From my findings I have tried hundreds (literally) of apps to manage my device, and in my humble opinion these 10 great apps, and 1 toolkit are invaluable, and are written by some very talented individuals...
1) ANDROID TUNER- Indispensable for so many reasons. It has the ability to do what dozens of apps do from editing build.prop files to widgets that display every conceivable statistic or state your device could possibly show. It is my number one app, and I can't imagine how many thousands of hours this developer has, and continues to, put into its creation. In addition to a phenomenal app this developer offers support to his customers that should be charged for, but isn't.
2) SD MAID- A serious device cleaner, methodical, in-depth, and intense. Constantly being updated and improved. Matthias offers a free, paid, and even a beta version for the more serious users. I have not found an app on Google Play that takes device cleaning and managing to this extreme.
3) FRANCO KERNEL UPDATER- Does as the name implies, it updates your Franco Kernel with a constantly new and improved version. It also offers kernel management, and a host of related options.
4) SUPERSU PRO- The SuperUser access management tool of choice by Chainfire. Completely manages superuser access for apps, as well as all superuser options necessary to provide a smooth administrative-level experience.
5) BUSYBOX PRO- by Stericson, is the ultimate busybox installer (and uninstaller) tool. With over 30,000 5-Star reviews on Google Play and something like 10 Million downloads. The only tool you need for everything to do with busybox. It keeps itself continuously updated, and offers Smart Install of all necessary applets.
6) ROM TOOLBOX PRO- As the name implies, this app is a virtual toolbox of dozens of apps useful in managing your device performance. JRummy Apps is constantly developing and updating the app to keep up with changing devices and technology. Everything from boot animations to root file and app management can be accomplished with this one app.
7) MX PLAYER- This app is the very best video player I have found, and I have tried about 20 of them. It offers an almost unlimited host of settings for every type of video out there. Lossy and lossless, with codecs for various devices, such as the NEON ARMv7 found in the Nexus 4, and the Nexus 7's Tegra 3. If you are serious about film, movies or video this is the app for you. I have not found a video I wanted to watch that this doesn't play, or a setting I wanted to tweak that this app wouldn't manage. A paid version with no ads is offered in addition to a free one.
8) TWRP MANAGER- This app is imperative for anyone with root access to their device. With root access you can break things and then your device doesn't work right. A recovery backup makes all that unimportant. If you get into trouble you simply flash a custom recovery and restore your device to perfect condition. Using Open Recovery Script, this app will backup, restore, wipe or copy your ROM for you very easily, and very fast.
9) TRICKSTER MOD- A kernel manager encompassing all aspects of kernel control. Works with all kernels. I use Franco kernels primarily for their dependability, performance and battery-life, and also Mirage for over clocking, and sometimes the stock android kernel. No matter which one you use this app will provide you with the tools to tweak them and it does it perfectly every time.
10) FING NETWORK TOOL- Overlook has created a really great app for the Network Administrator, or anyone that uses WiFi. This app is a complete Network Management Tool. It will map your network and provide all the information you need to know what devices are connected to which access points, the security levels, SSID, BSSID, Gateway, DNS, ping tests, trace route, wake on LAN, and does this with a great user-interface which keeps track of all information. FING will even alert you to changes in your network state. I find the app invaluable and have used it for several years. They even offer a subscription service which enhances the functionality of the app for a small monthly fee, however the app itself is free and completely functional.
*One additional note:
In order to root my device I have used Wug's Nexus Toolkit. I rooted my first device manually using ADB the first time and let me tell you this toolkit, which installs on any Windows PC, Laptop, or Tablet, is the best thing there is when it comes to rooting your Nexus device. It retains information about all your devices and updates itself as well as automatically downloading the latest android ROM, OpenRecoveryScript, Boot image, and installs them with just one click. This program unlocks your Bootloader, backs up your device, apps, and settings. It is a free download from his site, however there is a link for donations which I have happily contributed to twice since downloading this invaluable program.
Try these out, they really are worth your time. If you already know about them, great. If not you will save yourself some time and be able to go directly to installing a great app the first time.
Interesting new app that I'm pretty excited to see.
A peer to peer file transfer/sharing service that requires no login, no password, no account etc. Machines are paired via a temporary 6 digit code that expires if not used. No file size limit!
Secured with https, cross platform, cross device, and also works from their home page using just about any browser. I've used it windows<->android, android<->android and windows<->windows (via browsers). All you need is internet access.
Files are never stored on any server.