Apple has released the fourth public beta of iOS 11. or iPhone and iPad users. The finished version is due this fall and will be a free software update. 

iOS 11 has been in developer beta testing since early June. If you’re not already signed up for the public beta program, you can do so at https://beta.apple.com/sp/betaprogram/ . The public beta program is free, but remember: beta software is unfinished software so use with care.