meaning the gap between the keys ? there is no "standard" actually, i found a balance which seems pleasant to me, that's all

i've drawn themes with thinner gap, and others even without buttons

so just do as it looks good to you
note : think about low-res devices : if the gap is too big, the buttons will be too much thin, and the result could be ugly.
by the way, Cyril, is there a way to include ldpi pictures in the zip, like we can already do for hdpi with the drawable-hdpi folder ? i know the android sdk support it, but it seemed not to work in smart keyboard last time i gave a try.
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