Wired doorbells are not quite as easy to install as their wireless counterparts, but they are far from difficult and you don't have to worry about losing power unless your whole house loses power. Since most homes already have doorbell wiring, installing a video doorbell is as easy as removing your old doorbell, disconnecting the two wires, connecting your new doorbell to the wires, and attaching it to the outside of your house. In most cases you can connect the doorbell to an existing chime box as well.
Using this app, you can create awesome green screen videos. PowerDirector also comes with tutorial videos for all of its functions. Most of its features are available in the free version, but upgrading to the full version allows you to remove watermark, ads, and even to extract videos in 1080 and 4K resolutions. It is supported in Android 4.3 and above.
Signal Private Messenger is one of the most popular privacy chat apps. It features end-to-end encryption for all messages, voice calls, and video chats between two Signal users. It focuses a lot on individual chats. There are group chat features, but it's mostly for personal use. This is one of the biggest differences between it and rival privacy chat app Telegram. Video calls worked fine in our testing so we have no trouble recommending them. It's a neat way to get some encrypted chats as well. The app is also completely free and open source. You can't really go wrong with it, but there are better video chat apps if you need group video chats.