Wireless bluetooth problem with Iphone & Samsung S4 / ACE2. A little tricky with the blackberry. A board (set at 50% volume on the Jabra and control the volume from your phone). The result will be better. It is not very far from the last 8 hours announced by the manufacturer (7am verified). The sound quality is good (note the bass that sometimes tend to saturate if the settings are incorrect ° A very good value for money.