If for example I design/build a widget for counting the number of hits to a website, can I track the users legally?
For the hit counter example, I could track the number of impressions to the hit counter and on which sites the hit counter is on using Google Analytics Events feature. I would then know what sites use the hit counter and how many impressions they get.
Is this legal if I provide terms of conditions of use explaining my website tracks the usage of the widget they will be using?
Sounds legal to me in most countries, though IANAL.
I take it you are honest in the hit counting and collect only hits and maybe the http referer, not IP or other details. Not like social buttons that could track users.
If I would use the widget on a site I would expect some benefit from sending you that info. E.g. if you would share tracking stats for a number of sites of my kind, cause I must assume the info would be sold anyway.
