MobilePhoneOrchestra.com is an online web application developed as a platform to enable performances of fixed polyphonic contemporary art music for mobile phone orchestra. The ambition is to create a new performance paradigm for fixed electronic music in multiple parts to be performed in concert halls as stand-alone electronic orchestral music or in combination with soloists or traditional orchestra settings. The participants of a mobile phone orchestra are using their mobile phones or tablets and are performing on specially developed music instruments provided online on the MobilePhoneOrchestra.com website. Animated music notation gives performance instructions and conducts a performance and are also provided on MobilePhoneOrchestra.com. A mobile phone orchestra should for best performance consist of approximately 20-60 people or more regardless their musical background and age. 60 minutes of rehearsal are needed before a performance.