Smart Tools is the complete package of 6 individual apps. It has 6 sets below for a total of 15 tools. In a word, All-in-One. Set 1. Length, Angle, Slope, Level, Thread: Smart Ruler Pro. Set 2. Distance, Height, Width, Area: Smart Measure Pro. Set 3. Compass, Metal detector, GPS: Smart Compass Pro. Set 4. Sound level meter, Vibrometer: Sound Meter Pro. Set 5.