If you want to increase the storage on your Amazon 4K Firestick (Any Fire Device that support OTG), then follow the steps below
Tools Needed
- OTG Cable
- OTG Cable USA – https://amzn.to/36KWocN
- OTG Cable UK – https://amzn.to/2X14F8a
- USB 3 Flash drive
- USB drive USA – https://amzn.to/2CpSrMD
USB drive UK – https://amzn.to/2WWIJLa
- USB drive USA – https://amzn.to/2CpSrMD
Connect the OTG to your device and plug in your USB drive.

(APK at the bottom of the page)
1. From the Main Menu scroll to hover over Settings.

2. Click My Fire TV.

3. Choose Developer Options.

4. Click Apps from Unknown Sources.

5. Choose Turn On.

6. Go to About — Network and confirm your IP Addresss

Install the APK from the link below
Software Needed
Read Full Guide here on how to expand storage