SendHub started out slowly as a mass communication underdog, but with a million texts under its belt and 100% monthly user growth, it’s quickly becoming a viable Google Voice alternative. The company’s desktop and mobile services enable users to reach an unlimited number of contacts simultaneously. This comes in handy for everyone from conference organizers contacting attendees to team coaches trying to contact players.

The Y Combinator-backed company recently added calling and voicemail to its basic broadcasting and text messaging services. True, there’s an endless supply of calling-enabled iPhone apps (thanks, Twilio), SendHub allows users to do it from two phone numbers — for free.

That’s because SendHub believes in the divide between business and personal communications. Give out your personal SendHub number to friends and family, and an additional number for work contacts to be printed on your business card.

It’s a difficult market to crack because of the carrier stranglehold on the market, which has even forced Google to move slowly. In spite of this, I’m bullish on SendHub because the company understands how to use the web properly for the service. Not only has the company put a lot of effort into the website, but it has also pushed to make sure that all features are available online, which is something that Google Voice can’t claim. This means that for those that don’t have phones or those with a dead battery, calls can still be made from everywhere there’s an Internet connection.

Combined with the ability to send text messages, SendHub starts to become attractive as a service. The only problem that I have with it so far is the mobile app. After trying out SendHub just after it launched May, the HTML5-based app was understandably buggy. And even though the app has installed a meaningful development, it is still a pain to use because it is buggy, and the design is noticeably bad at first use. The company hired someone specifically to fix it and is pouring all of its resources into improving the mobile experience.

The company is is still growing despite its bad mobile app. According to cofounder Ash Rust, SendHub has powered 1 million text messages since its launch earlier this year, with 500,000 messages sent per month and 100 percent user growth month-over-month. Three percent of its users pay for premium features.

SendHub is also tweaking its message. When I first spoke to Rust earlier this year, the company was all about broadcasting information. Now, the emphasis is on being a communication tool. As of today, SendHub is renewing that focus with special homepages for schools, sports teams, and businesses, to sell its services as a communication tool for the groups.

But once they’re done with the homepage, they really need to get on that mobile app.

SendHub has raised $2 million in venture backing from Kapor Capital, Menlo Ventures, 500 Startups, Social Leverage Fund, and a number of angel investors.