Starting today, back number 's largest arena tour ever, "All Our Yesterdays Tour 2017," begins! To celebrate, we've prepared a smartphone game for back number fan club "one room" members to enjoy during the tour! "one room studio" is a smartphone game where you create and play back number albums. ▼ What is one room studio? It's a smartphone game where you create original albums that back number has released to date. You'll record the parts of Iyori, Kazuya, Hisashi one by one in order to complete one album. Once you've finished recording one person's part for an album, you can read their story about that time. And once you've finished recording all three parts and completed an album, you'll be able to see never-before-seen footage from the time of that work! Furthermore, if you complete all five albums...!? Stay tuned for more information. ▼ Game Navigator "アンコールWat-chan"アンコールWat-chan, the guardian deity of the studio, will make a special appearance to help you with your recordings if you record for five consecutive days! However, conversely, if you skip recording for more than two full days, you'll upsetアンコールWat-chan and the album production will revert to its original state. Please be careful. 'one room studio' allows you to learn more about back number while working on albums released so far. Please enjoy it in conjunction with the tour, as you look back on various back number songs and the past! Click here for details.