I have concluded that Eddystone and iBeacon may each have their uses - at least if I want to have the best possible beacon support in my Android + iOS apps.
It seems to me it would be simplest to have physical beacons that work with both - but since beacons are very new to me, I am not sure if they will be feasible:
Since I have zero experience with beacons, it is difficult had to evaluate the different maintenance aspects.
If you do not have day-to-day access to where beacons are placed - is it possible to acquire beacons that can do both without requiring constant maintenance?
While both iBeacon and Eddystone work well on Android, there are real disadvantages to using Eddystone on iOS, as detection times in the background are much slower, and it is not possible to launch a non-running app into the background on iOS with Eddystone. For iOS, Eddystone is best used with foreground-only apps.
From a beacon hardware perspective, both formats are similar. Hardware beacons come in battery powered and wall-powered variants. For best responsiveness and best distance estimating capability, it is important that the beacons be configured to transmit at their highest advertising rate and power.
If you do not have physical access to the installed beacons to change batteries, use wall-powered or USB-powered beacons if at all possible. Be very wary of manufacturer claims of battery life lasting a year or more. These claims are often based on low advertising rates and power levels that save battery but adversely impact performance for many use cases. Also, if both Eddystone and iOS are configured for transmission at the same time, battery life is cut in half.
If you use wall or usb-powered beacons maintenance is minimal. The main problem is people unplugging your beacons (e.g. to get a wall socket to use a vacuum or to get a spare USB port to plug in another device.) You can use locking covers over your beacons to help prevent this, but you cannot eliminate the problem entirely.