If you are looking for an alternative to your device's default camera app, you should check out the Nomao Minimalistic Camera app. This has a simple and basic interface but also has a lot of functional features. You can also use this to edit photos from the gallery. You can easily change the size or aspect ratio of the photo and change its palette.

This app is great for capturing photos as well as recording videos. You can use it with or without flash, just like a regular camera, and tap to focus. It is suitable for Android smartphones and tablets.