Most improvements reach you automatically: NEXO updates itself in the background, so you don't need to visit the store.
Occasionally a bigger change needs a new version from the store. If your installed version can no longer receive automatic updates, NEXO shows a full-screen message with an Update NEXO button. Tap it to open Google Play, install the update, then open NEXO again. Your data is safe, since it's saved to your account.
This screen currently appears on Android only.