Comparison

51SMT vs Crisp

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

Head to head
About

51SMT

Features
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51SMT is an industrial internet platform for electronics manufacturing. It offers a full suite of tools and services including community forums, equipment maintenance, document lookup and a parts mall. Meanwhile, it builds transaction information circulation channels for the electronics manufacturing sector to boost operational efficiency across the industry.

About

Crisp

Features
Read full description

Clear water. Test your speaker. Verify the result. Crisp uses targeted sound frequencies to help eject trapped water and dislodge dust from iPhone and iPad speakers. Then it listens with the microphone to compare real Before/After dB measurementsβ€”so you can check the result instead of guessing. NO ADS. NO ACCOUNTS. 100% OFFLINE. Is my data private? Everything runs on your device. Nothing leaves your iPhone or iPad. No accounts, no analytics, no ads, no tracking. How do I get started? 1. Place your device face down on a soft surface 2. Set volume to maximum 3. Tap Start Eject and wait 3 minutes What can I do with it? - Eject trapped water using a 165Hz tone, or switch to Dust mode to shake out lint and debris - Choose Normal, Turbo, or Deep intensity for a faster or more thorough clean - Find your phone's exact speaker resonance point with Resonance Finder for a stronger clean - Compare a real Before/After dB reading, not just a guess, to confirm the cycle worked - Generate any tone from 20Hz to 22kHz β€” up to 30kHz in Ultrasonic mode β€” with sine, square, triangle, or sawtooth waveforms - Test speaker frequency response with bass (80Hz), mid (1kHz), and treble (8kHz) presets - Run stereo balance (left/right) tests on stereo-capable devices - Check your microphone for blockages with a one-tap diagnostic - Measure ambient sound level with the built-in dB meter - Sweep frequencies automatically to dislodge stubborn dust particles - Take a structured hearing test across the audible range and save your audiogram - Save your favorite frequencies for one-tap recall - Set a cleaning reminder and track your streak over the past 7 days - Ask Siri to eject water, hands-free - 100% no ads, ever β€” most speaker-cleaning apps are free with ads until you subscribe; Crisp never shows one What devices does it work on? iPhone or iPad running iOS 17 or later. The same audio principles work on any built-in speaker. Why use Crisp? Speaker grilles trap moisture from sweat, rain, pool splashes, and humidity. Dust and pocket lint accumulate over time. Crisp uses sound vibration β€” the same technique built into Apple Watch β€” to physically dislodge particles without opening your device or using cleaning tools that can damage internal components. Does it really work? Sound vibration ejection is a well-documented technique. Results depend on how much water is trapped and how recently. For best results, run the cycle within an hour of water exposure, repeat 2 to 3 times, and keep the device face down throughout. How much does it cost? Download free. Optional Crisp Pro plans and any eligible introductory offer are shown in the app using your local App Store price. You can manage or cancel subscriptions anytime in Settings. Terms of Use: https://taxlite.net/crisp/terms.html Privacy Policy: https://taxlite.net/crisp/privacy.html

Screenshots

51SMT4 screens
Crisp4 screens

Verdict

The call

The clearest difference is iOS requirement: 51SMT at 13.0 against Crisp's 17.0. On price, update cadence, ads and in-app purchases there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. 51SMT sells 3 one-off in-app purchases and Crisp sells 4 in-app purchases, starting at $2.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

51SMT ships an update every 3 weeks, Crisp every 2 months. The most recent releases landed on November 3, 2026 and October 28, 2026 respectively.

Scorecard1 real difference Β· 5 level
51SMT versus Crisp: the parameters behind the verdict, then further details
Parameter51SMTCrisp
PriceFreeFree
Update frequencyEvery 3 weeks β€” betterEvery 2 months
AdsNoNo
In-app purchasesYesYes
DevicesiPhone, iPodiPhone, iPad
Requires iOS13.0 β€” better17.0
Further details β€” not scored
Size55 MB3 MB
Age rating4+4+
DeveloperSHENZHEN 51 SURFACE MOUNTING TECHNOLOGY CO., LTD.ZHENGQIAO JIANG

In-app purchases

3 purchases

51SMT

One-time3
  • ε‘¨δΌšε‘˜$0.99
  • ζœˆδΌšε‘˜$0.99
  • ε­£εΊ¦δΌšε‘˜$2.99
4 purchases

Crisp

Subscriptions3
  • Weekly3 Days trial$2.997 Days
  • Monthly$5.991 Month
  • Yearly3 Days trial$34.991 Year
One-time1
  • Lifetime$99.99

Questions

Is 51SMT free?
51SMT is free to download, with in-app purchases available.
Is Crisp free?
Crisp is free to download, with in-app purchases available.
Do 51SMT or Crisp have ads?
Neither 51SMT nor Crisp shows ads.
Which is updated more often, 51SMT or Crisp?
51SMT ships an update every 3 weeks, and Crisp every 2 months. Most recently, 51SMT was updated on November 3, 2026 and Crisp on October 28, 2026.

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