Rock Climbing Guide 27 Crags is a free iPhone app developed by 27 Crags Oy. It is a lifestyle app in the sports category that allows users to discover rock climbing topos created by local climbers from around the world. With this app, users can browse through sport, trad, and boulder areas on a world map, plan their climbing trips, and download topos for offline use (only available with the Premium subscription).

The app also features an in-app GPS function that helps users easily find their way to crags and boulders. Users can track their climbs with a tick list and plan future climbs with a to-do list. Additionally, users have the ability to create their own topos and share their knowledge of their home crags with others.

The app offers both free and Premium topos. Free topos can be created and published by anyone, but may not always have up-to-date information. Premium topos, on the other hand, are created by knowledgeable climbers who ensure the information is accurate and current. By subscribing to Premium, users not only gain access to the best and most accurate climbing information, but also support the climbers who create the topos, as 50% of the subscription profits are shared with them.

Overall, Rock Climbing Guide 27 Crags is a comprehensive app that provides climbers with a platform to discover, plan, and contribute to the climbing community. Download the app now and start exploring over 30,000 climbing spots shared by climbers worldwide.