We are a non-profit and are looking at mobile payment solutions to use during our fundraising events. Do most Square users use iOS or Android? What version of each do you need at a minimum?
the majority use iOS. Android is hit and miss on support due to the thousands of different Android devices available and the different hardware specs and the OS version and bootloader implemented by each device.
as far as what version you need iOS most of the hardware from the last 5 years can still run the latest updates, but I'd say you want to stay with hardware released in the last 3 years. here is Square's guide. https://squareup.com/help/us/en/article/3887
