New Pokémon GO Update 0.31.0 & Changelog

Here are the details of the new update:

The update is currently live on the Google Play Store, version 0.31.0.
The update is currently live on the Apple Appstore, version 1.1.0

Changelog:
- Avatars can now be re-customized from the Trainer profile screen
- Adjusted battle move damage values for some Pokémon
- Refined certain Gym animations
- Improved memory issues
- Removed footprints of nearby Pokémon
- Modified battle damage calculation
- Various bug fixes during wild Pokémon encounter
- Updated Pokémon details screen
- Updated achievement medal images
- Fixed issues with displaying certain map features
- Minor text fixes

Undocumented Changes:
- Removed Battery Saver Mode from the iOS version
- Favoriting a Pokemon prevents transferring

Info sourced from reddit