AngleMetric
EntropyMetrics: Contact Angle
Only for iPhone
Free · In‑App Purchases
iPhone
Measure how liquid beads or spreads on a surface, right from your phone. Check if a coating worked, a plasma treatment took, or if a material is hydrophobic.
Put a drop of water on a surface and watch what it does. On a clean pane of glass it flattens out. On a waxed car hood it beads up into a little dome. That shape — how much the drop sits up or spreads out — is the contact angle, and it tells you a lot about the surface underneath.
Contact angle is one of the oldest measurements in surface science, and for a long time you needed a benchtop instrument that costs as much as a car to get a number out of it. This app does the core of that job with the camera you already carry.
Here's how it works. You put a droplet on your sample, line the phone up, and the app finds the edge of the drop and fits it to theoretical curves. You get the contact angle in degrees, left and right sides, plus a fitted profile drawn over the live image so you can see exactly what it measured. There's a side-on mode for the classic profile view and a top-down mode for flatter, more wetting drops where you enter the volume and it works back to the angle.
Who actually reaches for this:
A grad student checking whether the oxygen plasma run actually changed the surface energy, before committing a whole experiment with it.
An engineer qualifying a coating or a cleaning step and needing a number to put in the report.
Anyone comparing materials — is this polymer more hydrophobic than that one, did the treatment hold up after a week, is the surface as clean as it's supposed to be?
And also curious people in the kitchen (where much of surface science was founded). Contact angle is a nice way to show a kid why rain sheets off a freshly waxed surface but soaks into an old one, how succulents collect water, how a butterfly keeps its wings clean.
What you get:
- Side-on and top-down measurement modes of droplets (as small as 5µL with newer phones)
- Contact angle in degrees
- A gravity-adjusted Young-Laplace numerical fit that can work with larger droplets
- Local Machine Learning droplet identification and profiling
- Live overlay so you can see the fit on the real drop
- Records saved on your device, with CSV export for your own analysis
Lighting, focus, and a steady hand all affect the reading, same as any optical method. Used carefully it's repeatable and quick, which is often exactly what you need when measuring in the field, on unwieldy or oddly shaped samples, or for a quick check. A low-cost 10-100µL micropipette is an excellent accompanying purchase.
Free to try. A one-time Pro purchase or subscription removes limits and adds unlimited measurements, saved records and exports. An Analytical Lab plan adds an auditable 21 CFR Part 11 enabled database, biometrics, data webhooks and a guided ASTM D8597 measurement flow for teams that need process discipline. Due to the nature of the program phones with an ultra-wide angle lens (i.e., iPhone 11+) image small droplets better.
Ratings & Reviews
The developer, BABAK SANII, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- BABAK SANII
- Size
- 63.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 14.0 or later.
- iPhone
Requires iOS 14.0 or later. - iPod touch
Requires iOS 14.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Analytical Lab / Enterprise $200.00
- Pro Monthly $1.99
- Lifetime Pro Purchase $19.99
- Copyright
- Copyright © 2026 Babak Sanii
