USB-C Tester: Charger & Cable

Find out why your phone charges slowly, which cable is throttling you, and exactly what your phone can do over USB-C.

USB-C Tester is a focused utility that combines the four checks every Android phone owner actually needs in one clean, ad-light app, without the fake "wattage" numbers, screen-spamming interstitials or paywall fragmentation you get elsewhere.

WHAT IT DOES

• Live charging meter: real-time voltage, current and battery-input wattage, with OEM-aware unit correction for Samsung, Xiaomi and Pixel quirks.
• 5-second charger test: a clean 0-100 verdict for any charger + cable combo. Save the result, name the cable, compare it next time.
• OTG check: confirms your phone supports USB-OTG, then verifies it actually works when you plug a real device in.
• DisplayPort Alt Mode check: finds out whether your USB-C port can drive an external monitor, and confirms it the second one is connected.
• Cable library: keep notes on every cable you own, tag them by colour, see at a glance which one charges fastest.
• Charging session history: full voltage / current / wattage curves over time so you can see thermal throttling and PD renegotiation in action.
• Charge alarm: get a notification when the battery hits 80% or 85% to extend long-term battery life.
• Live wattage widget: see your current charging speed without unlocking the phone.

HONEST ABOUT LIMITS

Android does not expose USB Power Delivery contract details to third-party apps without root. The wattage you see is measured at the battery, not the wall, typically 5-20% lower than the charger's wall rating because of conversion losses inside the phone. Anyone claiming to read true wall wattage on a stock Android phone is fudging the number. We label everything as "battery input power" so you always know exactly what you are looking at.

WORKS ON

Compatible with Samsung Galaxy S22 / S23 / S24 / S25, Google Pixel 8 / 9 / 10, OnePlus 11 / 12, Nothing Phone, Xiaomi 14, Motorola Edge, and most modern Android phones with USB-C running Android 9 (Pie) or newer. Works with Power Delivery, PPS, SuperVOOC, HyperCharge and other fast-charge protocols, wattage is reported as the phone reports it.

PRIVACY

USB-C Tester does not collect personal data such as your name or email, and your measurements stay on your device. It uses Google AdMob for ads and Firebase Analytics for anonymous usage statistics. AdMob may use an advertising identifier subject to your consent choice and Android settings.

WHY THIS APP

Built by a solo developer tired of charging-meter apps that spam interstitial ads, fake their wattage readings, or only do half the job. USB-C Tester does exactly what it says: measures what Android actually exposes, is upfront about the rest, and gets out of your way.