Twilio's first-mover advantage and best-in-breed reputation give it an edge against smaller competitors, such as Vonage's Nexmo and Bandwidth. The bears once claimed that those rivals would derail Twilio's growth -- but its revenue growth is still accelerating, its ecosystem is expanding (both organically and inorganically), and it recently achieved non-GAAP profitability.

3 Cloud Computing Stocks to Buy in 2019

And these competitors all focus on the developer market and some of them offer many or most of the same features as Twilio. What the competitors lack is the breadth of offerings developers can find on the Twilio platform. The competitors such Bandwidth, or Karix or Clickatell can all be used to build applications and they are generally much cheaper in terms of software cost when compared to Twilio. But they are all-point solutions. They don’t compete in all of the functional areas offered by Twilio.

Twilio: An 'Overvalued' Stock That Isn't Overvalued - Twilio (NYSE:TWLO) | Seeking Alpha