In Google Analytics for Android is possible to have a nice table like this one (and is built-in):
It seems however that I'm unable to find the same kind of report in Google Analytics for Browser..
How can I build the same report?
Sadly, this is not possible in the browser-based GA interface. The closest you can get is to make a custom report with
Users as metric and
Day of Week followed by
Hour as dimension drilldowns. But this will only get you data, not the heatmap.
In order to get heatmap, you need to export data into something else. This article has a tutorial on how to do it with Google Spreadsheets and mentions the very same report from mobile GA as you did. IMHO it is the next best thing, as long as Google does not make any updates within browser-based GA reports.