How to export game for APPLE IOS? (Do I need a Certificate?)

I'm finally making progress on (hopefully) successfully exporting my Construct 2 game to Android and hopefully having it work on Amazon.

Of course, now I'm curious how to do this so that people with APPLE tablets can play my game. I use the program called "Intel XDK" to export my Construct 2 games for Android -- but I see it also does give me an option to export as APPLE ios file. However, when I try and export it for apple I get this message:

IOS CERTIFICATE SIGNING REQUEST (CSR) iOS apps must be digitally signed with a certificate and private key pair.

Is there a FREE way to export games so people with APPLE devices can play my Construct 2 games? If not, what is the cheapest/easiest way to get a 'certificate' so my friends with their APPLE tablets could play my game?

Thanks in advance.

Just export to html5, and find a host, dropbox, gamejolt, itch.io, clay.io.

Safari should be pretty much up to app speed with ios8+.

Is there a way I can save my game into a single file so I could email it to friends with apple so they can download and install it instead of having to go to other sites? For example, on android, I think I can send people my .apk file via email, they click on it, and then install it on their tablets pretty easily.

Is there a way to do that for Apple folks? I'm not exactly sure how to export it for apple.. I did it once before somehow but found a directory full of tons of files.. so I'm hoping I only need one file I could email to folks with apple.

Nope, other than hosting it on dropbox, and sending a link to the index.html