The Steem blockchain was frozen for a while due to a bug in transfers allowing negative withdrawels.
The Steemit team was on the ball and a patch has since been released.
We just upgraded our servers to v.0.19.5. making us amongst the first 30 witnesses to do so.
If you support us please vote here for @blockbrothers
you can also choose to set blockbrothers as your proxy at the bottom of the page (fill in blockbrothers in the field)
or use either of the below links to do so automatically using steemconnect.
Vote for @blockbrothers via SteemConnect
Set blockbrothers as your proxy via SteemConnect
or apply for the Android beta here: firstname.lastname@example.org