When we choose apps to include in our roundups, we're after those that primarily excel in two areas: function and design. A functional app is either unique in its capabilities or simply works better than others. Apps with great designs are a joy to use. Android 9.0 Pie introduced a good range of app-specific improvements, so we also prioritize those apps that use new system features and reflect the latest visual styles. Droid Apps
There are a lot of apps out there that pay lip service to security and privacy, but Signal was built from the ground up with the goal of letting people easily communicate without having to worry about being overheard. The Signal app is a complete phone and SMS client replacement (though it works just fine as a standalone app, too) for sending and receiving encrypted calls and messages. A recent update has greatly improved the app's look and feel, proving that security and usability don't have to be at odds. Droid App
Facebook Messenger Kids might seem like it’s built for kids, but it’s really built for parents. With the app, parents have control over their kids’ contact list, and messages can’t be deleted — meaning that parents can check in to take a look whenever they want. Of course, there are some pretty sweet features for kids, like kid-appropriate stickers, GIFs, emojis, and so on.
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. Droid App