I looked for this before posting. The messaging has been disabled from legacy scoutbook, but the Scoutbook Plus messaging will not allow a mobile user to scroll to add people to the distribution list for the message. You can add who you see displayed, but if you have more people to sent a message than on that screen, your only option is invite all or just those people. I thought this had been pointed out and added to the list, but I cannot find that message in the search, so wanted to check to see when that function would be fixed as it all but eliminates the use of the message function in Scoutbook plus.
@AndrewPlatte - I just tested this on my android tablet and was able to scroll through the recipient list. I just used my finger within the box for the name and swiped up and down several times.
Must be a safari issue only for iPhone. I just checked with Firefox and the scrolling works.