Texpad is not available for Linux but there are some alternatives that runs on Linux with similar functionality. The best Linux alternative is LyX, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to Texpad and seven of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to Texpad are TeXstudio (Free, Open Source), Texmaker (Free, Open Source), TeXworks (Free, Open Source) and TexitEasy (Free, Open Source).
LyX is a document processor that encourages an approach to writing based on the structure of your documents (WYSIWYM) and not simply their appearance (WYSIWYG). LyX combines the power and flexibility of TeX/LaTeX with the ease of use of a GUI.
TeXstudio is an integrated environment for writing LaTeX documents. Our goal is to make writing LaTeX as easy and comfortable as possible. Therefore TeXstudio has numerous features like syntax-highlighting, integrated viewer, reference checking and various assistants.
The TeXworks project is an effort to build a simple TeX front-end program (working environment) that will be available for all today’s major desktop operating systems—in particular, MS Windows (XP and Vista), typical GNU/Linux distros and other X11-based systems, and Mac OS X.
GNU TeXmacs is a free scientific editing platform designed to create beautiful technical documents. It provides a unified and user friendly framework for editing structured documents with different types of content: text, math, graphics, slides, etc.