So glad you asked this question!
Disciplr is a web-application. Unlike the apps you download from the Apple or Google Play stores (those are called native-apps), you can only access the Disciplr app by going to Disciplr.com/app (or clicking Sign-In at Disciplr.com). As you may have guessed by the name, a web-app is available exclusively via the web (aka The Internet) and you have to be connected to be on the web, so...yes.
Now we know that some churches (fewer and fewer) have technology challenges, especially when it comes to reliable wi-fi in the classroom. So for those of you wanting to teach your lessons in a non-digital (otherwise known as "print) version, be sure and take care of that before class begins. All lessons have a print feature and any resource you might want to have handy in print can also be downloaded within the Resource Library for that lesson and then printed out.
Of course, the best Disciplr experience can be accomplished by using a laptop or tablet in the classroom. Saving time and money! In the near future, Disciplr will be providing information on our blog and tutorials in our help section to help get you started toward some not-too-expensive ways of outfitting your church or group-learning environment with technology that can help you get the most from your awesome interactive curriculum subscription, so keep an eye out!