There's no doubt to anyone that knows me, I'm an Android Fanatic. I wear the shirts, I have the gear, I hack the gear, I am the... well... no I'm not an Android, and I don't want to be one... but I think it's awesome.. *picture of me covered in Android stuff toys and tablets*
To date, I think I have 10 tablets, not to mention phones dating back to the original G1 (HTC Dream). But this is no trip down memory lane, it's a list, MY list of essential Android apps to get rolling with any new Android device that I have.
There's no such thing as STOCK Android unless it's just the bare Operating System and Google Apps... but even so a bare Android install still needs to get updates.... and the first thing that you get before anything else will probably be Google Play Services.
Google Play Services gives you access to the full suite of Google Apps and also helps you to jump over the slow update cycle of the major manufacturers (I'm looking at you, Samsung).
After the onslaught of Google Apps* updates are complete, or once they've gotten started, I tend to hover over to my desktop browser to start throwing the apps that I need / want onto the new device. Of course you can, with newer models of the OS, get the backup set of apps from any other device; most people will do this. I do not usually want to have go through 100 app possibilities to figure out what I do and do not want. Plus, it is smart to consider how much memory you have on this latest device. 8 GB is a very small margin for 50 apps, especially games.
*Google Apps includes: Chrome Web Browser, Drive, Docs, Sheets, Maps, Plus, Photos
Netflix. Netflix is pretty easy to install, but Amazon Video is not. Amazon Video resides outside the normal Play store for Google. To get it, you will need to install (2a) Amazon Underground first, which requires that you allow "non-play store" apps. To do this, Go to Settings --> Security --> Unknown Sources (slide the bar / check the box). Android will warn you, but you already know what it means (it means that you need to be very certain of where the app comes from, if not the Play Store).
Google Cast. And the obligatory (5) IMDB app, to use in searching for the actors in each movie. Google Movies and Amazon Video do provide info on the characters in each movie, but I still like to read further from my new device.
UtilitiesTraffic Monitor. It has a nifty widget that I use on the desktop that shows Mobile and WiFi data as well as an icon to do a speed test.
Another tool that does not usually get updated on the first sign of Internet is (7) Google Keep. It's a simple tool similar to Evernote, but not as robust as Google Docs. The files it stores allows me to track notes across all devices that have the app and my account, and for me to access the info from any net-connected computer with a browser.
Financial Calculators is my primary and only choice for this at the moment. For ages I used the free version, then realizing that I had more than surpassed the typical usage, I bought the Pro version ($5). The app includes a great little 4 x 4 space widget calculator that includes a button to access all the other calculators.
Some manufacturers include a skin over the stock User Interface of Android, Samsung for example, is no stranger to this. Within that skin sometimes the manufacturer will include a file explorer app of their own making, and sometimes there is nothing. It seems to depend on the base-line price of the tablet or phone as to whether one is included. I tend toward using (9) Astro File Explorer. It is a capably program able to carry out the moving and copying actions expected in an explorer program. The program can also track file usage and offers cloud storage.
Finally, the most often used tool, (10) Power Toggles. I have this installed on literally every device that can take it. It adds functionality to the window shade; that is to say that it adds additional buttons. Most Samsung tablets offer a series of functions in the shade like WiFi, Bluetooth, Screen Lock / Unlock, but often they are tied to the User Interface (UI) and are not removable or alterable. And in some other manufacturers devices there is no UI. I setup this app to show the following icons (a) Camera, (b) Screen-On Lock, (c) Brightness, (d) Hangouts, (e) Screen Rotation, and (f) Google Play store. On devices that have mobile data and / or a camera flash, I include these buttons.
CommunicationsHangouts app and before that other messaging services like Google Talk, AIM, and Skype. I use this app daily for text chat with family and video chat for work. If anything it is the quintessential application that makes the smartphone, a communications device.
ConclusionAfter these all other apps have added functionality, but at the bare minimum I want the above listed. I use most of the core Google Apps suite as well, but they usually come pre-installed.
It takes some time to set up a new device, but without these apps, I can't truly use a new device. And with so many devices, it's nice to know that they are more ubiquitous than a laptop or palm-top might have been 20 years ago. I can only wait to see what the next 20 years offers (hopefully better VR)