I have a 2016 4R, and an Android tablet with bluetooth, and disabled the seatbelt chimes on my 2016 using the following approach:
1. Purchased this bluetooth ODBII dongle that plugs into your vehicle:
https://www.amazon.com/gp/product/B005NLQAHS/ref=oh_aui_detailpage_o00_s02?ie=UTF8&psc=1
2. Paid $10 for the following Carista app by installing it on my Android tablet, and then connecting to the dongle (above) using bluetooth.
https://play.google.com/store/apps/details?id=com.prizmos.carista&hl=en
The Carista app will also work with iOS devices, but looks like you'd need to buy a different ODBII dongle than the one above. There are numerous settings that you can set on your 4R using Carista. I don't recall all of them.
BTW, other apps can also use the ODBII dongle, such as "Torque", etc... Check them out if you're interested.