With my personal experience of what I am using right now is Trillian and this also works like a email client.*And in my opinion this is even better than Google talk
I will list down some features from its official website and few screenshots
for your reference.
This is available as gratis and paid

Features
- Continuous Client
Your chats go with you everywhere. Trillian even keeps your phone quiet when you're active at a desktop!
- Interoperable
With support for Google Talk, Facebook, MSN, AIM, ICQ, Yahoo!, and more, stay connected with everyone.
- Device Support
Trillian is available on Windows, Mac, iPhone, iPad, Android, BlackBerry, and directly in your web browser.
- Email
POP3, IMAP, and native IM mail integration. New mail alerts and basic mail management are all exposed.
- Social
Never miss a beat with Trillian's social integration, keeping you connected to Facebook, Twitter, and LinkedIn.
- Tabbed Chats
Keep your desktop tidy with tabbed chats, featuring drag and drop support, unread indicators, and more.
- Message History
All desktop versions of Trillian come with a fully-featured message history viewer, including searching and filters.
- Spellcheck
Trillian's integrated spellcheck will always let you know when a word is misspelled and offer suggested fixes.
- Emoticons
Hundreds of amazing handcrafted emoticons for your chatting pleasure. Find them all, even the hidden ones!
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- Internationalization
User-created language packs and strong UTF-8 support help ensure a great experience in your native language.

Contacts

Note: To use any version of Trillian you'll have to have your own Trillian Account (formerly "Astra Account"), which keeps your settings synchronized between Trillian on your desktop, mobile devices and in-browser Trillian for Web which also another feature.
Hope my answer will help you to get out of Hangouts Chrome App ;)