Features: ───────. Direct reading in dB and dBA. 30 to 130dB+ range. Min/Max dB values displayed. Time weighting selection. Mic calibration. Vibrating dB alert. Graphing function. Meter rotation. 2 meter faces. 8 backgrounds. No full-screen ads. Free. NOTE: This app can measure sound level in decibels using your device's microphone located on the bottom.