Rodrigues, ÉlvioCarreira, MicaelGonçalves, DanielMagalhães, Luís and Santos, Beatriz2020-12-112020-12-112020978-3-03868-131-1https://doi.org/10.2312/pt.20131347https://diglib.eg.org:443/handle/10.2312/pt20131347In order to improve the text entry speed and error rate on tablet devices, we developed and tested 5 virtual keyboard variants. Some variants try to avoid errors by highlighting the next four most probable keys, either by changing its width or its color. Other variants were designed to decrease neighbor substitution errors, by shifting users' taps or by increasing the underlying area of the keys, based on its probability. The developed keyboards were tested by twenty young adults. Results show that soft keyboards without visual changes are the fastest method for text entry. Also, the use of word prediction further decreases typing speed, without improving the error rate. The Shifted and Size Invisible variants reduced neighbor substitution errors by 48.65% and 62.96%, respectively. Further improvements on error rate remain possible if we combine the strengths of multiple variants into one single variant.Textentry performancemultitouch tabletstyping speederror typespreattentive interfaces10.2312/pt.20131347135-142