DTMF Decoder vs Blue Box

Turns your iPhone into a simple DTMF decoder. Simply hold the iPhone's microphone near to a clear source of DTMF tones (telephone "Touch Tones") and it will display the numbers being dialed. The decoded digits are also placed into a text area from which you can copy them to the clipboard. See it in action here: https://www.youtube.com/watch?v=l_QD8KFCJPw Source code freely available: https://github.com/veghead/ios-dtmf-decoder

Blue Box is utility for encoding and decoding DTMF (Dual-Tone Multi-Frequency) or Touch Tone signals. Generate tones by using the phone style keypad or decipher tones using the device’s microphone. Tone combinations can be played back with adjustable tone, delay and pause lengths and volume. Choose from US, UK and Europe based systems. Enable Multi-frequency tones, which were a precursor to DTMF. Additional trunk control signals will be available including KP, ST1, ST2, ST3, KP/ST2. Additional tones include the Dial Tone, Ring Back Tone, Busy Signal and 2600Hz. A comma can be used as a pause character to provide extra time between tones during playback. Save and organize any number of sequences for easy recall using the Favorites feature. Choose numbers from your contacts to display and play back tones. Share an encoded or decoded number with the Phone, FaceTime or Messages app. Use Red Box mode to play coin tone sequences, including 5¢, 10¢ and 25¢ for the US system and 10p and 50p for European systems. Create a custom tone with control over individual frequencies and volumes. The custom tone can consist of any number of on and off pulses and can optionally be continuous. Record interactions with the encoder and play them back with the same timing. The recording feature works with all tones, including the dial tone, busy signal, ring back tone, 2600Hz and coins and trunk control tones. A help manual is including, with step-by-step instructions for all features. When the app is first run, pop-ups will be displayed indicating what the controls are used for. Warning: Blue Box is designed as an educational tool and utility. Do not attempt to use Blue for any illegal or malicious purposes. Blue Box can be used to assist in dialing numbers, but can not be used to manipulate digital telephone utility services. Limitations: Blue Box is software based decoding and is processor intensive. Performance may vary between devices. Tones that are less than 100 ms with pauses that are less than 100 ms are difficult to process in software. Future versions and processors may increase the reliability of faster tone sequences. If you need touch tone decoding for higher speeds, a hardware solution is recommended. Blue Box can not play tones into the iPhone phone feature while in a call. Blue Box is useful for entering numbers into touch tone operated systems such as an answering machine passcode or a dial-up service that requires the entering of several touch tones to navigate a menu system. Simply enter the numbers once and then play back the numbers into the phone's microphone with a touch.