Listening to the Game via iPhone
AM 1300 in GR has Brandstatter and Beckman for the games.
I've never been able to find the station on iHeart but I've heard it's there. I live in OH but I don't think that matters. You can also get the Big Ten Network app and if you upgrade it ($7.99) you can listen to all of the big ten football radio broadcasts. I've been listening to Illinois against tOSU. It's severely delayed but it works great.
I had a big problem trying several different radio apps and couldn't get the feed so finally broke down and paid the $8 (!!!!) for the app from the Big ten which streams the feed of every big ten game - usually the home feed I think - but at least I could listen.
Just saw an ad for the big ten network app that allows you to listen to every game. The app is free, not sure if the game are as well.
edit: just downloaded. The broadcast is an upgrade of $7.99
I can confirm that using the iheartradio app, and going to the station in Grand Rapids does work. I used this system last week on my android and it worked fine, and it is free. I would think it should work fine on your iphone.
Hope this helps.