1. Home
  2. Topics
  3. Diagnostic

Best Diagnostic Apps

221+ iOS apps curated and reviewed

4.5 avg rating
20 free apps
Updated July 2026

Every iPhone needs a few good diagnostic apps. We benchmark 221+ of them on App Store rating, freshness, and pricing, then surface the standouts so you don't have to scroll the App Store yourself.

Top Picks for Diagnostic

Apple Support#1

Apple Support by Apple Inc.

We’re here to help
Editor's Choice
🔧 Utilities
3.9😐(32K ratings)
FreeAds
Apple Support screenshot 1
Apple Support screenshot 2
Apple Support screenshot 3
Apple Support screenshot 4
Apple Support screenshot 5

Access personalized solutions for all your Apple products and services in one convenient app. Troubleshoot issues with guided steps, chat with support, manage subscriptions, reset passwords, and find nearby service locations for Genius Bar appointments.

What We Love

  • 👍 Helpful and friendly support staff
  • 🚀 Quick response and resolution of issues
  • 💡 Useful troubleshooting features
  • 🔒 Secure and trustworthy service

Room to Improve

  • 🐛 Buggy and unreliable app performance
  • 🤖 Lack of knowledgeable support staff
  • ⏱️ Long wait times and repeated transfers
Device Monitor²#3

Device Monitor² by Marco Ricca

System activity info
Worth Considering
🛠️ Developer Tools
4.7😊(9K ratings)
FreeIn-App Purchases
#29in Developer Tools
Device Monitor² screenshot 1
Device Monitor² screenshot 2
Device Monitor² screenshot 3
Device Monitor² screenshot 4
Device Monitor² screenshot 5
Device Monitor² screenshot 6

This app provides comprehensive system activity information for Apple devices, including detailed insights into hardware, sensors, and network status. It offers privacy controls, customizable widgets, and advanced testing and reporting features through optional in-app purchases.

What We Love

  • 🚀 Effective RAM cleaning
  • 🔍 Detailed device information
  • 🔧 Useful toolkit features
  • 💰 Fair one-time pricing

Room to Improve

  • 🐛 RAM cleaning issues after updates
  • 🔌 High background battery usage
  • 🕰️ Slow RAM cleaning process

More Diagnostic apps to explore

4
Phone Doctor Plus
Phone Doctor Plus
Phone Doctor Plus
by iDea Mobile Tech Inc.
Free

Diagnose over 40 hardware and system issues with this app. Monitor your phone's hardware, battery, memory, and storage. Track network usage and daily charging cycles to keep your device running smoothly.

40+ hardware diagnostic testsSystem monitoring (hardware, battery, memory, storage)Daily battery capacity and charging cycle recording
🔧 Utilities
(325)
ad-supported
5
System Status: hw monitor
System Status: hw monitor
System Status: hw monitor
CPU,battery,disk usage info
Free

Monitor your device's core performance metrics with this utility app. It provides real-time information on battery status, disk usage, CPU load, and network connections. Customize your view with light or dark themes and receive instant updates on system changes.

Graphical battery level displayDisk usage monitoringReal-time CPU usage
🔧 Utilities
(2.4K)
ad-supported
6
RepairSolutions2
RepairSolutions2
RepairSolutions2
by Innova Electronics
Free

This app provides comprehensive vehicle care and repair information for car and truck owners, DIYers, and technicians. It offers diagnostic capabilities with compatible OBD2 scanners and a vast database of verified fixes from ASE Master Technicians. Users can also access free vehicle maintenance information and schedule repairs.

OBD2 scanner integrationVerified repair databaseDiagnostic trouble code definitions
🔧 Utilities
(33K)
free with in-app purchases
7
Car Scanner ELM OBD2
Car Scanner ELM OBD2
Car Scanner ELM OBD2
The best OBD2 diagnostic tool!
Free

Monitor your car's performance, diagnose engine issues, and view sensor data in real-time. Customize your dashboard with gauges and charts, and reset fault codes. Supports a wide range of vehicles and offers advanced features for specific car brands.

Real-time sensor dataOBD fault code reading and resettingCustomizable dashboard with gauges
🔧 Utilities
(31K)
free with in-app purchases
8
Phone Diagnostics by SpotsPOS
Phone Diagnostics by SpotsPOS
Phone Diagnostics by SpotsPOS
Diagnostic Tool Made Simple
Free
🔧 Utilities
(0)
9
Car Scanner | OBD Auto Doctor
Car Scanner | OBD Auto Doctor
Car Scanner | OBD Auto Doctor
OBD2 diagnostics for ELM 327
Free

Diagnose your car's engine light issues and monitor real-time performance data. This app allows you to read and clear diagnostic trouble codes, track fuel consumption, and view sensor data. It's a comprehensive tool for understanding your vehicle's health.

Read and clear OBD2 diagnostic trouble codes (DTC)Reset Check Engine LightMonitor real-time vehicle data and sensor readings
🔧 Utilities
(6.1K)
free with in-app purchases
10
Deviapp - Device Diagnostics
Deviapp - Device Diagnostics
Deviapp - Device Diagnostics
Diagnostics and Safety
Free

Access detailed information about your device's software, memory, battery, and technical specifications. It also offers display diagnostics and a feature to block phishing sites for enhanced online safety and data protection.

Device information (software, memory, battery)Technical and physical characteristicsDisplay diagnostics
📊 Productivity
(480)
free with in-app purchases
11
PhoneTest.App
PhoneTest.App
PhoneTest.App
Better than PhoneCheck
Free

Diagnose hardware and system issues on your iPhone with comprehensive tests. Offers both quick and in-depth diagnostic modes to pinpoint problems.

Hardware diagnosticsSystem diagnosticsExpress test mode
🔧 Utilities
(6)
free
12
MyQuest for Patients
MyQuest for Patients
MyQuest for Patients
by Quest Diagnostics, Inc.
Free

Access your lab results, schedule appointments, and manage your health information securely. Find nearby locations, share data with providers, and even purchase your own tests. Take proactive control of your well-being.

View lab results securelyFind nearby Quest locationsSchedule and manage appointments
🏥 Medical
(466K)
free
13
M360 Diagnostics
M360 Diagnostics
M360 Diagnostics
by ATLAS SOFT Ltd.
Free

This utility app allows you to thoroughly test various components of your mobile device. It offers both automated and interactive tests to ensure everything is functioning correctly. Results can be emailed or shared directly with compatible service centers.

Component testingAutomated testsInteractive tests
🔧 Utilities
(6)
free
14
Device Monitor & Diagnostics
Device Monitor & Diagnostics
Device Monitor & Diagnostics
CPU, System, Battery,Temp Info
Free

Gain deep insights into your device's hardware and performance. Monitor CPU, RAM, battery, and sensors, and run diagnostic tests. Generate and export detailed system reports to optimize your device's health and functionality.

Detailed hardware informationSystem report generationDiagnostic tests
📊 Productivity
(73)
free with in-app purchases
15
BLE Diagnostic Tool
BLE Diagnostic Tool
BLE Diagnostic Tool
BLE Diagnostic Tool
Free

Connect to devices via Bluetooth to retrieve and display diagnostic data. Analyze information obtained through the protocol to troubleshoot and understand device status.

Bluetooth connectivityData retrievalProtocol analysis
🔧 Utilities
(1)
free
16
OBD2 Car Scanner - EOBD Facile
OBD2 Car Scanner - EOBD Facile
OBD2 Car Scanner - EOBD Facile
Torque ELM327 Diagnostic Tool
Free

Transform your smartphone into a professional car diagnostic tool. Read and clear engine fault codes, monitor real-time sensor data, and perform advanced diagnostics without a mechanic. Supports a wide range of OBD2 compliant vehicles.

Read and clear engine fault codesMonitor real-time sensor dataTurn off check engine light
🔧 Utilities
(4.9K)
free with in-app purchases
17
BitRaser Mobile Diagnostics2
BitRaser Mobile Diagnostics2
BitRaser Mobile Diagnostics2
Mobile Diagnostics
Free
🔧 Utilities
(0)
18
FIXD OBD2 Scanner
FIXD OBD2 Scanner
FIXD OBD2 Scanner
Clear Your Check Engine Light
Free

This app translates your car's diagnostic trouble codes into plain language, helping you understand potential issues and their severity. It provides maintenance reminders and offers advanced features like issue forecasting and emissions pre-checks with a premium subscription.

Translate check engine light codesUnderstand issue severityMaintenance reminders
🔧 Utilities
(26K)
free with in-app purchases
19
Pulse - Mobile Diagnostics
Pulse - Mobile Diagnostics
Pulse - Mobile Diagnostics
by Josh Mansfield
Free
🔧 Utilities
(0)
20
OBDeleven VAG
OBDeleven VAG
OBDeleven VAG
Scan your car & clear faults
Free

Transform your smartphone into a powerful car diagnostic tool. Easily scan, diagnose, and customize your vehicle's settings. Access advanced features like coding and live data to save time and money on car maintenance.

Advanced diagnosticsCoding and adaptationsOutput tests
🔧 Utilities
(6.6K)
free with in-app purchases

Related searches

diagnostic laboratory servicesdiagnostic imagingdiagnostic imaging northwestdsm-5-tr® diagnostic criteriadiagnostic imaging nwdiagnostic tool to check engine lightquest diagnosticsdiagnostic tooldiagnostic lab