Hello Nordic Support Team,
We have a product that uses nrf51422_CE_AA, Revision 3, 256KB ROM, 16KB RAM, PCA10028, SDK 8.0.0, S110. Since there are more than 7000 devices purchased, we deliver Firmware OTA updates to our customers via our iOS/Android/OSX App with buttonless DFU Bootloader (Dual Bank). Our product development started 2 years ago and now our firmware and hardware are mature enough after many revisions. Therefore we are in the stage of performance optimization. Our Firmware is 40KB (nrf-util distribution binary size) excluding Softdevice and Bootloader.
Now we are wishing to migrate/port to SDK v12 and Softdevice S130 because it improves a lot of aspects of the platform from our current SDK v8 and S110. Finally we should deliver the new Softdevice, new Bootloader and new firmware over-the-air to our 7000+ customers without bricking their devices.
Is it recommended to do such a migration with major SDK & SD revision? Our existing DFU Bootloader is dual bank, will it be able to update itself, the Softdevice and the firmware in an atomic process? Do our iOS/Android/OSX App need to update nrf SDK?
Please give us your suggestions.