Comparison

Bluetooth BLE Device Finder vs RF calculator & Smith Chart

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

Head to head
About

Bluetooth BLE Device Finder

Quickly locate misplaced Bluetooth devices using signal strength and a radar interface. Track devices in the background and receive notifications when they are lost, with the last known location recorded on a map.

Highlights
  • Find lost Bluetooth devices
  • Track devices in the background
  • Receive disconnection notifications
  • View last detected time and location
  • Use radar interface for proximity
  • Show signal strength and estimated distance
  • Display BLE device details
Features
Read full description

*** Now you can find your lost Bluetooth device quickly, before its battery runs out! *** This app can help you Find Your Lost AirPods, iPhone, iPad, AirTag, Apple Watch, and many other Bluetooth devices in seconds. Use it when you or your family misplace the device – and save the money you'd otherwise need to spend on a new one! HOW TO USE IT: 1. Run the app. Find and select your lost device in the list. 2. Move around slowly and keep watching the data (i.e., the signal strength and estimated distance) on the radar screen. When you get close to your lost device, the spot will turn red on the radar screen. 3. When the signal strength is over 90 and the estimated distance is 0 - 0.5m, look around. Your device won't be far away! Note: When you try to find your device, please walk slowly and watch the radar carefully. Find your device ASAP, or its battery will run out. Note: Your Bluetooth device must be powered on and within a detectable range. TRACKING FUNCTION: You may enable tracking for devices in the background by turning on the switch next to the device on the list. You will receive a notification when your tracked device is disconnected/lost. The application will ping the tracked devices from time to time and remember the last location and time the device was seen. KEY FEATURES: • Find your lost Bluetooth device (with BLE signal advertising). The app is easy to use! • Track your device constantly in the background with this app. A notification will tell you when your tracked device is 'Lost' (i.e., Disconnected). Also, the last detected time and location will be recorded for you. It's very useful when you’re travelling and want to keep your devices safe. ^ • Find your device using our radar. It's fun! No need to read a manual. ^ • Show hints, signal strength and the estimated distance between you and your lost device to help you find it quickly. ^ • Show the last seen (detected) time and last known location of your lost device on a map. ^ • Show your device's BLE (Bluetooth Low Energy) details such as UUID, RSSI, Services, etc. ^ • The following devices can be found/tracked by this app: - AirPods 1/2/3/4, AirPods Pro 1/2, AirPods Max - AirTag - iPhone 5/6/7/8/X/11/12/13/14/15/16, iPad 3/4/5/6/7/8/9/10/A16, iPad mini 2/3/4/5/6/A17Pro, iPad Air 1/2/3/4/5/M2/M3, iPad Pro 1/2/3/4/5/6/M4, iPod Touch 6/7 - Apple Watch Series 1/2/3/4/5/6/7/8/9/10/SE1/SE2/Ultra1/Ultra2 - Apple Pencil 1/2/Pro - MacBook, MacBook Air, MacBook Pro, iMac, iMac Pro, Mac Pro, Mac Mini, Mac Studio - Microsoft Gear, Band 1 & 2 - Samsung Earbuds, Galaxy Watch - JBL Tune, Vibe, Tour Pro, Charge, Flip 3 - Bellabeat Leaf - Garmin Watches - Many other Bluetooth headphones, earphones, and speakers (e.g. Bose, Sony, Google, Jabra, Logitech, Anker, Sennheiser, Technics, etc.) NOTE: The app can locate any BLE (Bluetooth Low Energy) device that is broadcasting a Bluetooth signal. ^ Requires In-App Purchase. Please contact support if you need help. Thank you! Privacy Policy: http://www.99mobileapp.com/pp.html Terms: http://www.99mobileapp.com/terms/index.html

About

RF calculator & Smith Chart

Features
Read full description

RF Calculator & Smith Chart is an all-in-one RF engineering toolkit for impedance matching, RF network analysis, antenna calculations, filters, attenuators and wireless system design. Built for RF engineers, electronics engineers, students, technicians and radio enthusiasts, it brings essential RF calculations and design tools together in one convenient app. Analyze impedance, work with Smith Charts, calculate VSWR and S11, design matching networks, estimate path loss, build RF attenuators and evaluate wireless links without jumping between multiple tools. RF & IMPEDANCE TOOLS • Smith Chart for impedance visualization and matching • S11 and reflection analysis • Reflection coefficient calculator • VSWR calculator • Impedance and transmission-line calculations • Cascaded RF network calculations IMPEDANCE MATCHING Design and analyze common RF matching networks: • L matching networks • Pi (π) matching networks • T matching networks • Stub tuner calculations Useful for antenna matching, RF amplifiers, transmission lines and other impedance-matching applications. RF FILTER DESIGN Calculate and design common passive and RF filters: • RC filters • RL filters • RLC networks • Butterworth LC low-pass filters • Chebyshev LC low-pass filters • Filter designs up to 8th order • Microstrip band-pass filters • Microstrip band-reject / notch filters RLC CIRCUITS Analyze frequency-dependent RLC networks: • Series RLC circuits • Parallel RLC circuits • Resonant frequency calculations • Frequency behavior and reactance RF ATTENUATOR DESIGN Quickly calculate standard RF attenuator networks: • Pi (π) attenuator • T attenuator • Bridged-T attenuator Ideal for RF signal-level control, impedance-matched pads and test setups. ANTENNA & PROPAGATION TOOLS Plan and evaluate RF and wireless systems with: • Antenna design utilities • Free-space path loss calculations • Friis transmission calculations • RF link budget calculator • Power density calculator • Radar maximum-range calculator COMPONENT DESIGN & REFERENCE Useful electronics tools are also included for RF design and prototyping: • Air-core inductor design • Spiral inductor design • Multi-layer air-core inductor calculations • SMD resistor code • Resistor color code • Resistors in series and parallel • SMD capacitor code • Capacitors in series and parallel BUILT FOR PRACTICAL RF WORK RF Calculator & Smith Chart is designed for quick engineering workflows. Select a tool, enter your parameters and get the values you need without working through repetitive equations manually. Use it for: • RF circuit design • Impedance matching • Antenna projects • Wireless link planning • Filter design • RF testing and troubleshooting • Electronics laboratories • Engineering study and coursework • Amateur radio and RF experimentation Whether you're checking VSWR, designing an impedance-matching network, calculating a link budget or experimenting with RF filters, RF Calculator & Smith Chart keeps essential RF engineering tools within easy reach.

Screenshots

Bluetooth BLE Device Finder4 screens
RF calculator & Smith Chart4 screens

Verdict

The call

The clearest difference is rating: Bluetooth BLE Device Finder at 4.4 against RF calculator & Smith Chart's 4.0. Bluetooth BLE Device Finder also leads on ratings volume (27K vs 1) and update cadence (every 2 months vs every 4 months). On price, 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Bluetooth BLE Device Finder sells 4 in-app purchases, starting at $3.99 per 7 days and RF calculator & Smith Chart sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Bluetooth BLE Device Finder holds the better App Store score, 4.4 against 4.0. That said, the two scores are not equally well evidenced: Bluetooth BLE Device Finder has 27K ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Bluetooth BLE Device Finder ships an update every 2 months, RF calculator & Smith Chart every 4 months. The most recent releases landed on November 7, 2026 and November 6, 2026 respectively.

Scorecard4 real differences · 6 level
Bluetooth BLE Device Finder versus RF calculator & Smith Chart: the parameters behind the verdict, then further details
ParameterBluetooth BLE Device FinderRF calculator & Smith Chart
PriceFreeFree
Rating4.4 (27K ratings) — better4.0 (1 ratings)
Positive reviews39.0% of reviews—
Number of ratings27K — better1
Update frequencyEvery 2 months — betterEvery 4 months
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.0 — better15.0
Further details — not scored
Size3 MB31 MB
Age rating4+4+
DeveloperRaymond NGAnas Abubakar

Customer experience

Bluetooth BLE Device Finder

All ratings27,302 ratings
Positive84.0%
Neutral4.3%
Negative11.8%
Written reviews292 reviews
Positive39.0%
Neutral3.4%
Negative57.5%

RF calculator & Smith Chart

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Bluetooth BLE Device Finder

Reported bugs

3 issues
  • Unable to detect certain Bluetooth devices like Apple Pencil
  • App crashes or freezes on some devices
  • Persistent pairing requests from unknown devices

Requested features

4 requests
  • Ability to name/label Bluetooth devices
  • Option to use feet/yards instead of meters
  • Improved device filtering and organization
  • More precise tracking and direction indicators

RF calculator & Smith Chart

Not enough reviews yet to summarise bugs or requests.

In-app purchases

4 purchases

Bluetooth BLE Device Finder

Subscriptions3
  • One Week Premium$3.997 Days
  • One Month Premium$9.991 Month
  • One Year Premium$14.991 Year
One-time1
  • Lifetime Premium$19.99
1 purchases

RF calculator & Smith Chart

One-time1
  • upgrade to pro$5.99

Questions

Is Bluetooth BLE Device Finder free?
Bluetooth BLE Device Finder is free to download, with in-app purchases available.
Is RF calculator & Smith Chart free?
RF calculator & Smith Chart is free to download, with in-app purchases available.
Which has better reviews, Bluetooth BLE Device Finder or RF calculator & Smith Chart?
Bluetooth BLE Device Finder is rated higher. Bluetooth BLE Device Finder averages 4.4 out of 5 from 27K ratings, while RF calculator & Smith Chart averages 4.0 from 1 ratings.
Do Bluetooth BLE Device Finder or RF calculator & Smith Chart have ads?
Neither Bluetooth BLE Device Finder nor RF calculator & Smith Chart shows ads.
Which is updated more often, Bluetooth BLE Device Finder or RF calculator & Smith Chart?
Bluetooth BLE Device Finder ships an update every 2 months, and RF calculator & Smith Chart every 4 months. Most recently, Bluetooth BLE Device Finder was updated on November 7, 2026 and RF calculator & Smith Chart on November 6, 2026.

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