Keys:

<Enter> Rolls dice.
<Left> Shows previous dice roll.
<Right> Shows next dice roll.
<1> One dice rolls (e.g. D6).
<2> Two dice rolls (e.g. 2D6).
<3> Three dice rolls (e.g. 3D6).
<4> Four dice rolls (e.g. 4D6).
<5> Five dice rolls (e.g. 5D6).
<6> Dix dice rolls (e.g. 6D6).
<7> Seven dice rolls (e.g. 7D6).
<8> Eight dice rolls (e.g. 8D6).
<9> Nine dice rolls (e.g. 9D6).
<0> Ten dice rolls (e.g. 10D6).
<*> Temporary toogle between singe digit mode and details. On next roll, default is used.
<#> Clear history.

Options:

Auto-roll when dice changes Automatically rolls dice whenever type is changed.
Always show roll details Shows all dices after roll. This is valid only when more than one dice is thrown. 
System beep on roll Produces system beep on each roll. Whether that sound will be heard or not depends upon your phone sound configuration.
Wait after roll (seconds): Number of seconds to wait after each roll. Until that number passes, no further rolls can be made.
Show exit Adds exit option to main menu. This option is pretty unnecessary because this application will automaticaly delete history or even exit if required in case of memory pressure. However, some people like to micro-manage memory usage themselfs  and this is option for them.