Swipe Up, you can use many kinds of formula.
Swipe down, you can see calculate hisotrys.
In calculator display swipe left of right, you can delete text.
You can choice Calculator Color Theme.
And ready to guide activity.

• infix
• postfix

• SlidingTabLayout
• AutoResizeTextView
• StickyListHeader(https://github.com/emilsjolander/StickyListHeaders) Custom
• SlidingUpPanelLayout(https://github.com/umano/AndroidSlidingUpPanel) Custom