If your smartphone doubles as your business phone, you'd probably kill for a second phone number. That's exactly what you get from Toktumi's Line2, a clever telephony app released in 2009 for iPhones -- and just yesterday for Android.
Line2 provides a new local number, a ported existing number, or an 800 number. All three options include free inbound and outbound domestic calling, free texting, free voicemail, and lots of other goodies.
The app supports tri-mode calling, meaning calls can travel over cellular networks, 3G/4G data networks, or Wi-Fi. And it switches automatically depending on the best available option.
Once you've installed the app and signed up for service (which, impressively, you can do right on your phone), calls to your new/ported/800 number come through more or less like regular calls.
The new Android version offers full backgrounding support, so you can receive calls on your Line2 number while you're running other apps. It also performs speech-to-text transcription for text messages, a cool perk the iPhone version doesn't offer.
You can try Line2 free for 30 days, after which you'll pay $9.95 per month or $49.95 for a six-month contract. (If you want an 800 number, you'll have to opt for the Toktumi Unlimited plan, which runs $14.95/month or $79.95 for six months. It also ) The app itself is free.
And pretty cool, especially for business professionals seeking a separate number that integrates with their existing phone. In my tests (of the iPhone version), it worked extremely well.
I should note, however, that Google Voice allows you to accomplish much the same thing, especially now that it offers number porting. I do think GV is a more complex solution, but it has the advantage of being, well, free.
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