HTC Gallery is an image gallery by HTC that is intended for HTC devices, but will also work on non-HTC devices as well. (Requires sideloading the .apk, as the app cannot be installed to non-HTC devices from the Google Play Store).
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Pro Offers interesting image effects
The app allows creating blended, kaleidoscopic or masked images.
Pro Built-in image filters
HTC Gallery comes bundled with image filters that allow the user to add image effects to their images. Functions similar to Instagram filters.