For developers, it could be a good source of extra income. That said, some developers have reported huge download numbers off the back of the free app of the day promotion, but no resulting increase in sales once the promotion is over. You are also likely to do better with tablet optimized apps than smartphone apps in general, as Kindle users are the primary customers.
Textra is an excellent alternative to Messages on Android. The app includes tons of visual customization options that you won't find with the stock messaging app, including custom contact colors, text bubble styles, and notification icons. Additionally, you get extra features such as text scheduling, the ability to blacklist contacts, and the option to rename group conversations. Textra also has excellent light and dark modes. Droid App
Despite the fact that we are well into the 21st century, paper still persists in offices. But Microsoft Office Lens lets you turn physical documents into digital ones using your Android. It can even capture doodles and notes from a whiteboard. If you want portable document scanning, but aren't keen on getting an Evernote account, this might be the solution for you. Droid Apps
This app is geared toward those who are looking for a real relationship, rather than a quick hookup or short fling. Every day at noon, you get sent a prospective match based on a specific set of criteria. You can Like them or Pass on. If you like them, you’ll be set up with icebreaker questions; if you pass, the app will learn your preferences and try again tomorrow.
File browsing is something everyone inevitably has (or wants) to do, so you might as well do it with a capable, fantastic file browser. Solid Explorer is pretty much as good as it gets in the file explorer apps realm. It features Material Design, archiving support, support for the most popular cloud services, and even some more power user stuff like FTP, SFPT, WebDav, and SMB/CIFS support. It looks great, it’s incredibly stable, and it just works well. There is a 14-day free trial with a $2.99 price tag at the end of it. This is, by far, the best file manager on Android for most people. Droid App