Here is an decibel meter for S60 5th and Symbian^3 devices. It uses to phones microphone to measure the sound level i dB and is quite accurate.
Enjoy!
Works with following devices: Nokia 5228
Nokia 5230
Nokia 5233
Nokia 5235
Nokia 5530 XpressMusic
Nokia 5800 XpressMusic
Nokia C6-00
Nokia N97
Nokia N97 mini
Nokia X6
Nokia C6-01
Nokia C7-00
Nokia N8-00
Nokia E7-00
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