TopGuru vs Engine Displacement Calc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
TopGuru
Transform your phone or tablet into a powerful vehicle diagnostic tool via Bluetooth. Access full system diagnosis, OBDII functions, bi-directional controls, and essential maintenance services for a wide range of car brands. Generate detailed diagnostic reports for efficient troubleshooting.
- Full System Diagnosis
- Full OBD2 Functions
- Bi-directional Control
- 8 Special Maintenance Functions
- AutoVIN Vehicle Identification
- Diagnostic Report Generation
- Wireless Bluetooth 5.0 Connection
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Easily link the app with your Phone or Tablet using Bluetooth, transforming your devices into a smart and high-powered diagnostic tool! Packed with essential features like complete OBDII functionality, all system diagnosis, Bi-Directional controls, AutoVIN, automatic diagnostic reports, and more, this Bluetooth OBDII scan tool is a must-have for technicians. Its versatility shines through with eight maintenance service functions and coverage for over 60 vehicle brands, making the product a portable and adaptable auto scanner. Main Features: 1. Full System Diagnosis: Covers Engine, Transmission, Airbag, ABS, ESP, TPMS, Immobilizer, Gateway, Steering, Radio, Air Conditioning, and more. 2. Full OBD2 Functions: works as an OBD2 code reader and performs all 10 modes of OBD2 testing free for life. 3. Bi-directional Control: Easily locate issues with active tests. 4. 8 Special Functions: Perform Oil Reset, Throttle Adaptation, EPB Reset, BMS Reset, and more. 5. Repair Data Library: Includes DTC Repair Guide, Technical Service Bulletin, DLC Location, Warning Light Library. 6. AutoVIN: Enables automatic vehicle identification for quick diagnosis. 7. Wireless Connection: Utilizes Bluetooth 5.0 with a range of 33 feet/10m. 8. Graphs, Values, and Dashboard-like Data Display: Ensures easy interpretation of information. 9. Generate Diagnostic Reports: Obtain detailed reports for Systems, Fault Codes, or Data Streams. 10. Pro version features 13 reset functions and IMMO capability. Terms of Use (EULA): https://plat.topdon.com/topdon-plat/out-user/baseinfo/template/getHtmlContentById?softCode=TopScan_DisplaySW_iOS&language=7&type=25
Engine Displacement Calc
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Need to know the exact displacement of an engine build before ordering parts? Whether you are verifying a crate motor, sizing a swap, or checking class compliance, this app calculates total engine displacement from bore, stroke, and cylinder count in seconds. Supports metric (mm) and imperial (inches). Shows total volume in cc, liters, and cubic inches. Includes bore/stroke ratio analysis with square, oversquare, and undersquare classification. FEATURES: - Enter bore diameter, stroke length, and number of cylinders - Instant per-cylinder and total displacement - Output in cc, liters, and cubic inches simultaneously - Bore/stroke ratio with automatic classification - Metric and imperial unit toggle - Works completely offline Perfect for engine builders, mechanics, race teams, and automotive enthusiasts who need accurate displacement figures on the spot.
Screenshots
Verdict
The clearest difference is price: TopGuru at Free against Engine Displacement Calc's $4.99. TopGuru also leads on chart position (#162 vs unranked) and iOS requirement (15.0 vs 17.0). Engine Displacement Calc's advantage is in-app purchases (none vs 30). On update cadence, ads 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
TopGuru is free to download; Engine Displacement Calc costs $4.99 up front. TopGuru sells 21 in-app purchases, starting at $9.99 per month. Engine Displacement Calc asks for nothing beyond the download.
TopGuru ships an update every 3 weeks, Engine Displacement Calc every 6 weeks. The most recent releases landed on October 27, 2026 and October 18, 2026 respectively.
| Parameter | TopGuru | Engine Displacement Calc |
|---|---|---|
| Price | Free — better | $4.99 |
| Rating | 3.5 (412 ratings) — better | — |
| Positive reviews | 29.3% of reviews | — |
| Number of ratings | 412 — better | — |
| Update frequency | Every 3 weeks — better | Every 6 weeks |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Best chart rank | #162 — better | — |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 15.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 2.2 GB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | HK TOPDON TECHNOLOGY Co., LIMITED | Shanghai Sheyuan Network Technology Co., Ltd. |
Bugs and requests
TopGuru
Reported bugs
3 issues- Incompatibility with certain vehicle models
- Login and account issues
- Unreliable Bluetooth connectivity
Requested features
3 requests- iPad optimization and full-screen support
- Expanded vehicle coverage, especially for motorcycles
- Ability to save and export diagnostic data
Engine Displacement Calc
Not enough reviews yet to summarise bugs or requests.
In-app purchases
TopGuru
- Monthly Auto-renewal$9.991 Month
- Monthly Auto-renewal$19.001 Month
- Quarterly Auto-renewal$24.993 Months
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- Annual Auto-renewal$49.991 Year
- Annual Auto-renewal$99.001 Year
- Renault Gateway 1-Token$11.99
- Diag Bundle Renewal3 variants$49.99
- TopGuru Diagnostic Bundle$49.99
Show 13 moreShow fewer
- TopGuru IMMO Bundle$49.99
- Renewal Bundle4 variants$99.00
- TopScan Pro Renewal Bundle3 variants$99.00
- Harley Moto Software$99.99
- Harley Moto Software Renewal$99.99
- Moto Diag Bundle Renewal-Moto$99.99
- Moto Diag Bundle$99.99
- Moto Diag Bundle Renewal$99.99
- 22 Special Functions Bundle2 variants$129.99
- Renault Gateway 10 Tokens$129.99
- Renault Gateway 5 Tokens$147.99
- 17 Special Functions Bundle2 variants$179.00
- FCA Gateway 1-year (EU only)$229.99
Engine Displacement Calc
No in-app purchases
Questions
Is TopGuru free?
Is Engine Displacement Calc free?
Do TopGuru or Engine Displacement Calc have ads?
Which is updated more often, TopGuru or Engine Displacement Calc?
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