Solid Explorer - Solid Explorer is a powerful Android file manager featuring access to most popular cloud storages, root access and easy extensibility.
Soulver - Soulver is a software application that functions as a calculator that allows you type a continuous stream of information rather than having to input data into multiple cells.
Amaze File Manager - Free and open-source Android file manager with no ads.
Numi App - Numi is a beautiful text calculator for Mac.
Total Commander - A Shareware file manager for Windows® 95/98/ME/NT/2000/XP/Vista/7, and Windows® 3.1.
Calca - Calca is an advanced symbolic calculator for iOS, OS X, and Windows that's as easy to use as a text editor.