First time Android user! (Need help :) )

I'm not sure on how efficient it is on Mobile, but for security I'm currently trying out Avast's Mobile Security & Antivirus

You should get a file explorer (to find files transferred between your computer and mobile easily, or nagivate the mobile's folders)
I use this: ES File Explorer File Manager
Games...
if you ever bought some Humble Bundles and they're playable on android, download HB's app.

Free games from Amazon Underground app

App that recommends games in specific genres: Fetch

Obv, Steam app

Alchemy Classic , Only One , One Epic Knight , Sword & Glory , Neko Atsume: Kitty Collector

You should try out some games that use tilting, they're fun. E.g Sheep Up

Optional:
flashlight apps, Tripadvisor, QR Code Reader, Dropbox, TunnelBear VPN

Languages -> Duolingo:

Educational -> Khan Academy

anything transport related apps for your area? (e.g we've got an app for my country's public transport (buses))

Period app (just incase) Period Tracker, My Calendar

Cool stuff I can't use in my country: Circle Pay [BTC related], Uber

need root
Titanium Backup ★ root
RepetiTouch Free

ReDungeon
https://play.google.com/store/apps/details?id=com.nitrome.redungeon
by nitrome.com

I use this:

https://play.google.com/store/apps/details?id=com.qihoo.security&hl=en_GB

Not sure if it is the best security app but seems good!

I recommend Nova Launcher or another custom launcher in order to create a more customized home screen than you would otherwise be able to. There are lots of cool icon packs that you can use to replace the default ones. I got some ideas by reading through some reddit threads of people showing off their homescreens like the following: reddit

Here's a picture of my homescreen, hopefully: home screen

I also like the the Moon+ Reader for reading pdf files and the alarm clock by the developer MacroPinch (I would link to the Play store if I wasn't on mobile, sorry).