[Plugin: NextGEN Public Uploader] Upload problems on iPhone

For some reason, the upload widget for my site when accessed on iPhone has “select file” greyed out — it won’t let anybody select photos and upload from their iPhone. It works fine on Android. I am not using a mobile version of my site — just the standard version.

Does anybody have any ideas? Thanks!

https://www.ads-software.com/extend/plugins/nextgen-public-uploader/