Yes it is completely free and with nothing added.

lmariec said

I went to Google Play and it wanted me to sign in, is it free?

James said

Yes it is completely free and with nothing added.

Actually my andoid tablet doesn't have a Google Play app so i can't download it:((

No problem!

You can download Firefox directly from Mozilla here: ftp://ftp.mozilla.org/pub/mozilla.org/mobile/releases/latest/android/

Or there's an open-source alternative to Google Play called F-Droid. You can use it to install Firefox (and lots of other free software too) and it will keep you notified of updates.

The ftp is not mirrored or load balanced so use http://download.cdn.mozilla.net/pub/mozilla.org/mobile/releases/latest/android/

Note that the Release and Beta version .apk installed manually will not get updates. So either you need to pay attention to when new Release come pout and manually install new version or you can use the Aurora channel which does get updates. http://download.cdn.mozilla.net/pub/mozilla.org/mobile/nightly/latest-mozilla-aurora-android/

The ftp link did not work and f-droid lead to Google Play which I don't have ??

Sorry about the FTP link. Try this link, as provided by James: http://download.cdn.mozilla.net/pub/mozilla.org/mobile/releases/latest/android/

Just click your locale (ie American English is en-US) and then download the apk file.

The download button on the F-droid homepage should give you an APK file you can install directly - no Google Play needed.