Hacker News new | past | comments | ask | show | jobs | submit login

You can weigh small objects with most smartphones with decent accuracy these days using the barometer. Put your phone into a ziplock bag, blow full of air, zip closed. Take a small object with known weight to calibrate your scale. Carefully place the object on the ziplock bag with your phone inside. The barometer in your phone can measure the air pressure change by having the weight placed on top of the bag. Knowing the weight of your first object and the change in pressure observed, you can calibrate the scale to know how much pressure change correlates to weight placed on top.

Then you can weigh arbitrary objects using your phone! Be careful, don't break your phone (don't try to stand on it to weigh yourself!)

On measuring things - I prefer going in the opposite direction and weighing even where it's unconventional.

I have a Melitta funnel for making single servings of coffee, but when I'm using it I can't see how full my mug is without lifting up, and they are mostly opaque, and the funnel doesn't hold a full mug's worth of water. So I started putting my mug, funnel, filter, and coffee on a digital scale with tare, and remembering how much each size holds in dry ounces. It avoids the situation in which I'm waiting for the water to run out to make sure it won't overflow; I just pour until I hit the right weight and then go do something else until it's done.

That's amazing - the accuracy of phone barometers is great, I found they could reliably detect the difference in pressure from raising or lowering the phone a meter or so.

The compass is still terrible though!

Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact