via Google Operating System by Alex Chitu on 1/22/09
Google has way too many separate implementations of Google Talk and very few features are available in all clients:| Features | Google Talk | Gadget | Labs Edition | Gmail Chat | iGoogle/orkut Chat | iPhone version |
| Requires installing software | Yes | Flash plug-in | Yes | No (some features require plug-ins) | No | No |
| Tabs | No | Yes | Yes | No | No | No |
| Themes | Yes | No | No | No | No | No |
| Gmail notifications | Yes | No | Yes | No | No | No |
| Multi-user chat | No | Yes | Yes | Yes | No | No |
| Offline status | No | Yes | Yes | Yes | Yes | Yes |
| Music track status | Yes | No | No | No | No | No |
| Audio chat | Yes | No | No | Yes | No | No |
| Voicemail | Yes | No | No | No | No | No |
| Video chat | No | No | No | Yes | No | No |
| File transfer | Yes | No | No | No | No | No |
| Send SMS | No | No | No | Yes | No | No |
| AIM integration | No | No | No | Yes | No | No |
| View photos (Flickr/PWA) | No | Yes | Yes | No | No | No |
| Play videos (YouTube/GVideo) | No | Yes | Yes | Yes | No | No |