Thank you for taking the time to post, and welcome to the Community!
You can play music to the SoundTouch 10 in one of 3 ways.
The first is by pairing to the SoundTouch 10 through Bluetooth. This will mean that any audio you play from the Iphone (Itunes, Spotify, Youtube etc.) would play through the speaker.
The second means is by using the AUX port on the system to directly cable up to your Iphone. Similar to above, any audio then played through the phone would play through the speaker instead.
The third method would be by connecting the system to your home Wi-Fi network, and then linking this back across to the Bose SoundTouch app. Then, any music service setup through the app can be used to play through the speaker.
I hope this helps, and please get back to me if you have any questions!