Just about everything is customizable on Android, even the lockscreen. Just in case you're bored of the drab ways you can spice up the part of your phone that you probably spend the least amount of time with, LokLok is a new lockscreen app that has just entered open beta as of yesterday, and is a connected lockscreen that lets you do more than just unlock it or read some notifications. In fact, it lets other people(close friends and family)interact with it too. LokLok is a way for you and others to share with each other simple connected messages via the lockscreen so those messages are literally the first thing you could see when you wake up in the morning and bring your devices display up from sleep mode.
Since the lockscreen is the first thing you see when pick up your device if its in sleep mode, an app like LokLok actually seems like a pretty great idea. It gives you less of a chance to be distracted and do other things before checking messages. Connect with other using LokLok and you can draw messages on each others screens and leave them little notes. You know that they'll see the message immediately because it'll be right there when they wake their device. You can even take pictures and have that be the temporary backdrop for you drawn message like they display in the video.
You can use the lockscreen just like a whiteboard, so whether you want to completely erase what you've drawn and start anew, or just add to a masterpiece that you've already began, feel free to do either. You can share your images and drawings over social media if you wish, but LokLok provides a healthy dose of privacy too since groups are completely private and other users won't have the ability to search for you, accepting invitations is the only way to connect. This does replace your standard lockscreen so keep that in mind, but if you love the idea of having a shared whiteboard with the people that you connect with most, then you should definitely check out LokLok. Since the app is open beta, some things are subject to change and there is a possibility of a bug or two. It's a beta remember so those things aren't out of the question. However if you do notice something you can help the devs address it by letting them know the issue exists. LokLok open beta is free.