15 months of use without worries, he notes all. I think it is clear as it gives the same result as other models, but even if it would not would be irrelevant, as it is to compare the days between them. He has more than 15 days of actual battery life (I've never completely discharged). It is small and can be lost, but no more than a bunch of keys. He happened to have mest synchronization problems with my phone, but not for several months and I havent lost anything he fact that has a multi-day memory. In short, it reminds me to order to move me and that's exactly what I expected.