Once bubble is stable, you can measure what you want. It is possible to use another way you can weigh it on an inclined plane, which then becomes a reference to check other sloped surfaces of the same nature. On the right side on your mobile screen, you have icon of a man. This icon is used to exit this application.
Molki Nivo is a flash based application. The current version is 21.0.025 which brings improvements over the previous versions. It's a freeware and you can get this app along with a document to understand this app.

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