Best practices for photo storage

I want to make an Android application that has the same look as Instagram, which means every profile has a gallery of photos.

My question is about storing and retrieve those photos. I want to know what is the best practice for photo storage in a database (MySQL), more precisely:

• Should I store photos with original size (2mb for example) or resize them with smaller size?
• Should I store them with two version (smaller size photo, and normal size photo)?

Saving images in the database looks like overkill, it's not needed. Saving on disk should be fine.

Although you should focus on your business logic & leave this to image libraries which does this stuff & do best for memory & performance.

Some famous libs are:

• Picasso
• Glide
• Universal image loader
• Fresco
• & you will find many more

Almost each library does lots of stuff for you, such as:

• In memory cache(LRU Cache) - so that UI thread is not blocked from doing I/O operation from disks
• Disk Cache - To keep images saved for further app sessions, also when memory cache reaches its limit its have to be evicted from it., you can specify disk cache size.
• Various image scaling strategies
• Image transformations
• Clearing up bitmaps for freeing up memory
• Network operations on background threads
• Background threads management & so on..

My suggestion is to go with one of the image library