Cloud APIs & SDKs for adding watermark for Microsoft Excel & OpenOffice Calc. Adding watermark for local Spreadsheets by the Cells Cloud API. SDK support kinds of development languages. They include Android, C#, Go, Java, NodeJS, Perl, PHP, Python, Ruby, and swift....Excel and OpenOffice Calc spreadsheet C# library to add watermark...Excel and OpenOffice Calc spreadsheet Use Cells Watermark REST...