Here’s a Wall Street Journal article by Katherine Boehret, which gives 10 simple ways to “smarten” your Android device.
Katherine suggest my two favorites: easy screenshots and contact shortcuts.
Katherine suggests you use Swype for your keyboarding activities, but I actually like SwiftKey. Remember though, her focus is on ease-of-use and minimizing tasks, so Swype makes sense.
One thing I’d caution you about though is using face unlock for security on your phone.
Although Google improved the feature in Jelly Bean with “liveness” testing, there are still flaws. What’s more, I find face unlock extremely temperamental, relying upon only the very best lighting, angle, and contrast conditions. Ultimately, I have to use my default pattern or password.
The best security measure, which Android shows in a worst-to-best list on your Android device, is password lock.
If you really need some lock-down-your-Android advice, check out this post.
Also, you can use my recommendations to learn about some ways to improve your phone.