Android itself owns three parts of memories which are system storage, internal storage, and SDCard storage (/ext-sd). So if you perform a hard reset toward your Android device then all data (photos, game data, files) within internal storage will be deleted.
Preparation before hard-resetting your Android.
- Make sure you have moved your photos, pictures, musics or other data from your internal memory to your memory card.
- Make sure you have backup all necessary data. Why you need backups? Well if something went awfully bad afterward then you can restore to previous condition.
- Make sure you battery power is sufficient because sky will fall if your device suddenly shutting down during hard-reset.
How to backup before hard resetting your Android device.
- Backup your contacts -> Open Settings -> Synchronize (Sync). Sync contact via Gmail or open the Contact app itself, then tap on Menu -> Export to Sdcard, move contact backup file (.vcf extension) to your Memory card. After you have finished hard resetting your device then you can restore your contacts by going to Menu then choose Import from SDCard.
- Backup your SMS -> Backing up SMS can be done by using an app namely SMS BACKUP & Restore. Be sure the backup is also being moved to SDCard before hard resetting your device.
Sure, but this kind of backup can only be performed if your Android phone is rooted. If you have a rooted phone then you can backup a certain app or game by using a popular app like Titanium Backup. Thus if you wish to use the app you get to firstly root your Android OS.