New Apple update rendered AmericanHeritageDictionary5 inoperable. As requested, I sent full purchase details & history, so they could "get me up & running" again. Then they just stopped responding. Don't waste your money on an app that will stop working, from a developer who just doesn't care enough to support it.
Update, August 2021
So now several months later, the developer responds that AmericanHeritageDictionary5 works fine, that support always answers emails, that I must have purchased a different version (??), and that maybe I didn't use the right email address. In other words, somehow it's my fault that, after working fine for years, the Apple iOS update was incompatible with AmericanHeritageDictionary5 . All my info was sent, twice, but somehow it's not enough, or not the right info, or sent to the wrong place. I have deleted AmericanHeritageDictionary5 & purchased the version from MobiSystems, which works just fine. Life is too short to waste time on a company that just doesn't care very much.