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WattCheck: Cable Tester

WattCheck helps you understand which charging cables and power adapters actually perform well. Have a drawer full of USB-C and Lightning cables? Not sure which one charges fast, which one is slow, and which one may be worn out? WattCheck makes it easy to test and compare your charging setup using real-world battery charging behavior. Start a test, keep your device connected, and WattCheck estimates charging performance over 5, 10, and 20 minute windows. Save results for each cable and charger, build a personal cable ranking, and quickly spot weak or inconsistent charging gear. KEY FEATURES • Charging Performance Test Run simple charging tests and see estimated speed in % per hour and normalized watt estimates. • 5, 10 and 20 Minute Results Get quick early feedback after 5 minutes, better accuracy after 10 minutes, and stronger comparison data after 20 minutes. • Cable Ranking Save tests for different cables and automatically rank them by performance. • Best and Weakest Cable Detection WattCheck highlights your best-performing cable and helps identify cables that may be slow, weak, or degraded. • Charger Comparison Name your power adapters and compare how different chargers perform with different cables. • Test History Keep a complete history of your charging tests, including cable name, charger name, device profile, battery change, duration, estimated power, and notes. • Charts View charging progress and speed charts to better understand each test. • Device Profiles Choose your iPhone or iPad model so WattCheck can use the correct battery capacity for better estimates. • Smart Warnings WattCheck warns you when a test may be less reliable, such as when battery level is above 80%, where iOS may reduce charging speed. • CSV Export Export your test history for personal tracking, troubleshooting, or comparison. HOW IT WORKS WattCheck uses public iOS battery information to estimate charging performance based on battery level changes over time. It does not require special hardware and does not use private system APIs. For best results: • Test between 20% and 70% battery • Use the same device when comparing cables • Use the same charger when comparing cables • Keep the device temperature normal • Run longer tests for better accuracy IMPORTANT NOTE WattCheck does not directly read USB voltage, current, or USB Power Delivery data. iOS does not provide this information to regular App Store apps. WattCheck estimates real-world charging performance based on battery level changes, making it useful for comparing cables and chargers in everyday conditions. PREMIUM WattCheck Premium unlocks unlimited charging tests, full history, cable ranking, charts, charger comparison, and CSV export. Use WattCheck to clean up your cable drawer, find your best charger setup, and stop guessing which cable is slowing you down. Subscription Plans: - Payment will be charged to your App Store Account at confirmation of purchase. - Your subscription will automatically renew unless auto-renew is turned off at least 24 hours before the end of the current subscription period. - Your account will be charged for renewal within 24 hours prior to the end of the current subscription period. Automatic renewals will cost the same price you were originally charged for the subscription. - Manage or cancel your subscription from your user settings in the App Store at any time after purchasing. - Any unused portion of a free trial will be forfeited if you purchase a subscription. Privacy Policy: https://sunteame.com/privacy-policy/ Terms of Use: https://sunteame.com/terms-of-service/ If you have questions or feature requests, use the support link in the app to contact us.