iOS
215 Street
Free - Unlimited (Previously $1)
Ally - Collect and Backup
Paid - $9.99 (Previously $4.99)
(Price doubled to promote Pro)
Ally Pro – Collect and Backup
Paid - $14.99
(Ally + Offline access)
Amii NFC
Paid - $0.99
Amiibomb - NFC Tool for Amiibo
Paid - $4.99
AmiiBoss Max
Free - Exponential timer, Third-party donation
(History of shady practices. Use with caution!)
Amiibox - Identify & Write NFC
Free, $9.99 premium or single use credit(s)
placiibo
Free - Single use demo -> Trial -> Subscription (?)
Tagmiibo: Write NFC Tags
Free - 5 writes, $8.99 unlimited
Umiibo
Paid - $0.99
3DS
Thenaya
Requires 3DS CFW (Custom Firmware)
Install Thenaya with FBI
Open FBI, select Remote Install, select Scan QR Code