Comparison

DTMFdec vs Blue Box

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

DTMFdec

This utility decodes DTMF tones, even in noisy conditions. It stores decoded numbers for easy actions like dialing, creating contacts, or copying to your clipboard for further lookup.

Highlights
  • Sensitive DTMF tone decoding
  • Adapts to noisy environments
  • Stores decoded numbers
  • Dial number directly
  • Create new contact
  • Add number to existing contact
  • Copy to pasteboard
Features
Currently charting
Read full description

DTMFdec is a highly sensitive DTMF-tone decoder which dynamically adapts to noisy or quiet environments. Decoded numbers are stored in a list, from where you can perform actions like: • dial number • new contact with number • add number to existing contact • copy to pasteboard Especially the "copy to pasteboard" feature is useful when you want to lookup the number in your local phone directory or just google for it. DTMFdec is able to decode the following digits: 1234567890*#ABCD Watch a demo video on the web site https://dtmfdecoder.app/demo/

About

Blue Box

Encode and decode DTMF signals using your device's microphone or keypad. Play back tone sequences with adjustable settings, and save them for easy recall. Explore various tone systems, including trunk control and coin signals, for educational and utility purposes.

Highlights
  • Encode/decode DTMF signals
  • Adjustable tone, delay, and volume
  • US, UK, and European tone systems
  • Multi-frequency and trunk control tones
  • Coin tone sequences (Red Box mode)
  • Custom tone creation
  • Save and organize sequences
Features
Currently charting
Read full description

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.

Screenshots

DTMFdec2 screens
Blue Box4 screens

Verdict

The call

The clearest difference is rating: Blue Box at 5.0 against DTMFdec's 3.4. Blue Box also leads on review sentiment (56% vs 33%) and update cadence (every 7 months vs every 25 months). DTMFdec's advantage is price ($2.99 vs $4.99) and iOS requirement (12.4 vs 15.0). On ratings volume, ads, in-app purchases and monetization model there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

DTMFdec costs $2.99 and Blue Box $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Blue Box holds the better App Store score, 5.0 against 3.4. Both are backed by a comparable volume of ratings — 5 and 3 respectively. Written reviews point the same way: 33% of DTMFdec's written reviews are positive against 56% of Blue Box's.

UpkeepUpdate frequency

DTMFdec ships an update every 25 months, Blue Box every 7 months. The most recent releases landed on August 15, 2026 and September 11, 2026 respectively.

Scorecard5 real differences · 6 level
DTMFdec versus Blue Box: the parameters behind the verdict, then further details
ParameterDTMFdecBlue Box
Price$2.99 — better$4.99
Rating3.4 (5 ratings)5.0 (3 ratings) — better
Positive reviews33.3% of reviews55.6% of reviews — better
Number of ratings5 — better3
Update frequencyEvery 25 monthsEvery 7 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
Best chart rank#195#192 — better
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.4 — better15.0
Further details — not scored
Size1 MB2 MB
Age rating4+4+
DeveloperJérémie BlaserSunshine Valley Systems

Customer experience

DTMFdec

All ratings5 ratings
Positive60.0%
Neutral0.0%
Negative40.0%
Written reviews15 reviews
Positive33.3%
Neutral6.7%
Negative60.0%

Blue Box

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews18 reviews
Positive55.6%
Neutral0.0%
Negative44.4%

In-app purchases

None

DTMFdec

No in-app purchases

None

Blue Box

No in-app purchases

Questions

Is DTMFdec free?
DTMFdec costs $2.99, with no in-app purchases.
Is Blue Box free?
Blue Box costs $4.99, with no in-app purchases.
Which has better reviews, DTMFdec or Blue Box?
Blue Box is rated higher. DTMFdec averages 3.4 out of 5 from 5 ratings, while Blue Box averages 5.0 from 3 ratings.
Do DTMFdec or Blue Box have ads?
Neither DTMFdec nor Blue Box shows ads.
Which is updated more often, DTMFdec or Blue Box?
DTMFdec ships an update every 25 months, and Blue Box every 7 months. Most recently, DTMFdec was updated on August 15, 2026 and Blue Box on September 11, 2026.
Which is more popular, DTMFdec or Blue Box?
DTMFdec currently peaks at #195 in the App Store charts, and Blue Box at #192. Chart position reflects recent download velocity rather than total install base.

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