Yes - Clever Contacts automatically detects which email clients you have installed on your device. Initially it is set to send emails via Apple Mail but you can change it to use any of the following email clients (assuming you have these installed on your device):
- Apple Mail
- Microsoft Outlook
- Yahoo Mail
Just tap on the "Settings" button at the bottom of the "All People" or group listing screens. Note: on an iPhone you may have to first tap the "More..." button to see the "Settings" button.
Then tap on the "Email Client" button and select the one you want to use.