FishRuler: Fish Size MeasureSupport
Questions or bug reports about FishRuler (fish size measuring)? Please take a look at the FAQ below, then feel free to email us. If measuring isn't working at all, the first thing to check is whether your iPhone has a LiDAR scanner.
FAQ
Which iPhones does it work on?
FishRuler measures with the LiDAR scanner, so it needs an iPhone that has one. That means the Pro models: iPhone 12 Pro / Pro Max and later. On a device without LiDAR you'll see "This device does not support LiDAR" and measuring won't be available. Please check your model before buying.
How do I use it?
Point the camera at the fish, tap once at the nose and once at the tail. A line is drawn between the two points and the distance appears in centimeters. If a tap is off, drag the marker to fine-tune it, and press Reset to clear the measurement for the next fish.
How accurate is the number?
The value on screen is an estimate based on what your device's depth sensor actually measures. You'll get steadier results in good light, with a steady hand, and with the fish laid as flat as you can manage. Treat it as a practical figure for use on the water.
Can I use it for tournament measuring or size limits?
Please don't use it for that. For tournament measuring rules, legal size limits, or official record submissions, always confirm with the measuring device the rules require. Checking the regulations that apply where you fish is up to you as the angler.
Does it work where there's no signal?
Yes. FishRuler runs completely offline. Rocky shorelines, mountain streams, jetties, offshore on the boat — it measures just the same with no service.
Is there a fee? Is it a subscription?
It's a one-time purchase. Buy it once and there's nothing more to pay. No subscription, no in-app purchases, no ads.
Are my photos or measurements sent anywhere?
No. FishRuler collects no data at all and sends nothing off your device. The camera feed is processed on the phone purely for measuring, and the app never saves it.