Speedy Spectrum Analyzer is a professional grade FFT/Spectrum Analyzer for Android users.

This app supports both lograithmic and linear frequency axis analysis. You can pan both horizontally and vertically by dragging. The app also features a smooth zoom feature. You can dynamically adjust FFT size up to 16384 bins (for 2-3 Hz accuracy!), based on the optimal size for your screen.

Other features:

• Exponential averaging (adjustable)
• Peak hold
• Share screen snapshots easily
• Range set - full audio range from 20Hz, up to 22kHz
• Peak & valley measurements with crossbar tools
• Adjustable dB levels for ceiling / floor

Changes in v3.06

• Peak Hold Overlay option
• Peak Hold long-press enable
• 48 kHz audio sample rate option (device dependent; will fall back to 44.1kHz if your device does not support 48kHz)
• Select between 'Default' and 'Front' mic (device dependent)
• for Toshiba Thrive & Dell Streak mic issue

Changes in v3.02

• Bug fix for bug introduced in 3.02
• Logarithmic option for frequency axis
• Peak hold reset option in menu
• Limit main peak display to viewable range
• Performance enhancements