vim-gutentags is a plugin that manages tag files for you in an asynchronous way. Tag files are used by the editor to provide the Go to definition for the identifiers in your code.
To use vim-gutentags, you need to have Universal Ctags installed in your system. This is the program that will actually generate the tag files. (The most popular program to do this in the past was Exuberant Ctags, which stalled in its development and has been superseded by Universal Ctags).
Once the plugin is installed, it doesn't require too much configuration (although it provides a number of settings that can be tweaked). You may want to take a look at the option below to not to pollute your code with tag files though.
Note that for the plugin to work, it needs to know the root directory of your project. For that, it will use the first parent directory of the current file that contains a .git, .hg or similar folder. However, if gutentags is unable to find the project root, then no tags will be generated. (If your code doesn't live in a repository or you want to specify how to find the root directory yourself, take a look at the g:gutentags_project_root configuration variable in gutentag's documentation).
vim-gutentags doesn't have any incompatibility with Vem.
In any case, one very useful option that you can set in your vemrc file is:
This will prevent the plugin from creating tags files at the root directories of your projects (which is the default).