{{ yourDate|date_modify("+1 day")|date("m/d/Y") }}
this code add 1 day to your date.
see http://twig.sensiolabs.org/doc/filters/date_modify.html
Just in case someone needs to add more than +1 day in a twig template
{% set sevenDays = date(yourDate)|date_modify("+7 days")|date("d/m/Y")%}
Once the variable set can be used anywhere in the template
This worked for me:
{% set tomorrow = 'now'|date_modify("+1 day") %}<input id="event_date" name="event_date" class="datepicker" type="date" value="{{ tomorrow|date('Y-m-d') }}" />