Which module should I use to manage translations in D7?
Excerpt from the Translation Management project page:

... provides complete workflow management for multilingual Drupal sites.
Content managers can manage all translations from one central page. The module shows which contents need translation and notifies translators about what they need to do.

Be aware however that this is a D6-only module, not at all suited for a D7 site.
For D7 there are basically 2 alternatives available:

Translation Overview, mentioned as a recommended add-on on the i18n project page also. From its project page:


... provides a table listing the site's nodes and showing what's been translated into each language. It also lets you assign priorities for translating nodes into the various languages.


Translation Management Tool, considered as the successor of the previous module, and &quot;the&quot; module to move forward with in D8 also. From its project page:


... provides a tool set for translating content from different sources. The translation can be done by people or translation services of all kinds. It builds on and uses existing language tools and data structures in Drupal and can be used in automated workflow scenarios.
This module does not make i18n or any other language module for Drupal obsolete. It does only facilitate the translation process.