1. A method comprising: outputting, by a computing device and for display at a display device, a graphical keyboard comprising a plurality of keys; receiving, by the computing device and from an input device, an indication of a selection of one or more of the plurality of keys; determining, by the computing device and based at least in part on the indication of the selection, a character string; determining, by the computing device and based at least in part on the character string, a plurality of candidate words; determining, by the computing device, and based at least in part on the plurality of candidate words and a plurality of features, a spelling probability that the character string comprises an incorrect spelling of at least one of the plurality of candidate words, the plurality of features comprising at least a spatial model probability associated with at least one of the one or more candidate words; and responsive to determining that the spelling probability satisfies a threshold, outputting, by the computing device, for display at the display device, the at least one of the plurality of candidate words.
18. The method of claim 1 , wherein the character string is a first word in a lexicon, the method further comprising: responsive to determining a context associated with the character string, selecting, by the computing device and based at least in part on the context, a second word in the lexicon as the at least one of the plurality of candidate words.