There are certain circumstances in which you might need a new phone number: You place an ad and don't want to disclose your personal number, or travel overseas and don't want to roam using your own number because roaming charges can get really high. This is when the iPlum app can come in handy: It gives you a US phone number on your iPhone, iPad, or Android device which you can use anywhere in the world.
iPlum doesn't really stand out from the crowd through its user interface – it looks dated when compared to other VoIP apps – but it does provide a solution that works. After signing up, you can decide whether to use the free version of the app or agree to pay $1 per month and reserve an available US phone number. By the way, you get 30 minutes’ worth of free credits at signup, which you can use to call or text any US number, and then it's 1 cent per minute for external calls. Calling and messaging between iPlum users is free.
iPlum was engineered for low-bandwidth usage and adapts to available data rates and latency of a broad range of Wi-Fi or cellular channels. During our testing (on Wi-Fi), the audio quality was good – nothing to complain about. I also liked the idea of converting the iPad into a phone: If the tablet is your productivity tool, sometimes it's convenient to be able to place/receive phone calls on it.
If you use up your initial 30 minutes’ worth of credit, you can buy 500 credits for $4.99 or 1000 credits for $9.99 via an in-app purchase. You can even change your phone number by deleting your current subscription plan and signing up for a fresh account with a new iPlum number.
To summarize: Don't expect too much from iPlum in terms of design, but if you are looking for a US phone number, you can have one for $1 per month. That's iPlum. Download iPlum for free from the App Store / Google Play.