Not usefull because of very bad translations
Most of the app is in broken English and all the picture descriptions are in another language.
Internet always required: Is my biggest annoyance/gripe, especially since each page is only a few kilobytes at most. Such a requirement is utterly pointless and a hindrance for those of us with spotty connections. The language support also seems fairly amnesiac: the app constantly forgets the last language. When coupled with the always online requirement, the problem becomes exacerbated.
Pretends it's in English, but it is in Spanish. Language select does not work well, and all diagrams I came across were in Spanish or were unreadable.
Good This is a very good free application I have never seen
Most popular electronics reference & calculator app for electronics enthusiasts.