Lambda vs Stellar BLE
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Lambda
This app helps musicians and sound engineers convert between musical notes, frequencies, and wavelengths. It features a dynamic fader, built-in oscillator, and frequency tracker with waveform display. Customize tuning standards and speed of sound for precise audio analysis.
- Convert notes, frequencies, wavelengths
- Dynamic fader for real-time adjustment
- Built-in oscillator with waveform
- Frequency tracker with waveform
- Customizable tuning standards
- Adjustable speed of sound
- Share data via standard methods
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Musicians and Sound Engineers. Musical Notes and Frequencies and Wavelengths. Now there's an app from dgApps to convert between them all. The app features a sliding fader to dynamically change frequency, wavelength and musical note, with locks to step through standard third octave frequencies or whole musical notes. There's a built in oscillator so you can hear the frequency, and a frequency tracker so the app can tell you the frequency. Both the oscillator and the frequency tracker display the audio waveform. A settings section allows for different tuning standards, and variations in the speed of sound. Lambda can also receive calculated Speed of Sound in Air values from another dgApps app, Cair. Lambda is now a universal app, equally at home on an iPhone as on an iPad. In Split Mode on an iPad device, side by side with Cair, the calculated Speed of Sound in Air is passed in real time to the Lambda app. Lambda allows you to share frequency/wavelength/note data via all the usual sharing methods.
Stellar BLE
Wirelessly control smart lights via Bluetooth. Adjust brightness and select from millions of colors to set the perfect ambiance for any room. Effortlessly manage your lighting experience.
- Bluetooth Low Energy control
- Turn lights on/off
- Adjust brightness
- Choose from millions of colors
- Wireless operation
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Stellar BLE - The smart way to control your Sansi bulbs. The Stellar Blue app allows you to turn your Sansi smart lights on and off wirelessly through Bluetooth Low Energy (BLE), adjust brightness smoothly and choose your favorite color among millions.
Screenshots
Verdict
The clearest difference is price: Stellar BLE at Free against Lambda's $2.99. Stellar BLE also leads on update cadence (every 3 months vs every 54 months) and iOS requirement (12.1 vs 15.6). Lambda's advantage is rating (5.0 vs 3.0). On ratings volume, ads, in-app purchases and device support 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
Stellar BLE is free to download; Lambda costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Lambda holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.
Lambda ships an update every 54 months, Stellar BLE every 3 months. Both last shipped on October 24, 2026.
| Parameter | Lambda | Stellar BLE |
|---|---|---|
| Price | $2.99 | Free — better |
| Rating | 5.0 (1 ratings) — better | 3.0 (1 ratings) |
| Positive reviews | 80.0% of reviews | — |
| Number of ratings | 1 | 1 |
| Update frequency | Every 54 months | Every 3 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.6 | 12.1 — better |
| Further details — not scored | ||
| Size | 6 MB | 75 MB |
| Age rating | 4+ | 4+ |
| Developer | dgApps | Shanghai Sansi Electronic Engineering Co., Ltd |
Customer experience
Lambda
Stellar BLE
In-app purchases
Lambda
No in-app purchases
Stellar BLE
No in-app purchases
