Campbell, 23, and Turner, 22, started the transcription service over the summer of 2018/19 as they spent 10 weeks at a startup programme run by Canterbury University.
In early 2019, Vxt was accepted into the Google Cloud Platform for Startups, where up to $150,000 of their costs are covered.
The pair went on to be named the Grand Winner of the university's annual 85,000 Startup Challenge.
And in December 2019 they were also accepted into Vodafone's Xone accelerator programme.
Today, Campbell and Turner employ 13 staff, five of whom are fulltime, and are looking to hire a machine learning specialist with their new funding (today, Vxt's transcription is around 90 per cent accurate, depending on cellphone reception and accent).
The startup also wants to build on its modest offshore presence (it already has users in the UK and Canada). A desktop version of its service is also in the offing.
Campbell is still trying to finish his degree - a double-major taking in physics and economics - squeezing part-time study into his schedule, while Turner graduated last year with an honours degree in computer science.
Vxt's next big step will be a Series A round, probably late next year. Campbell anticipates that will be a $2 million raise. He sees the startup becoming profitable around the same time.
Today, Vxt's app has been downloaded some 18,000 times.
Most use the ad-supported free version, which will transcribe five voicemails a month.
Campbell says there are also around 900 paying for premium versions of Vxt, which costs $2 a month (for 20 transcriptions plus Slack integration), $6 a month (50 transcriptions plus a voicemail to email option) to an unlimited plan with various bells and whistles for $13 a month.
The seed raise turned out to be hard yakka. The pair started in the New Year and had commitments for $200,000, but once Covid hit things dried up completely.
Auto-transcribing voicemail might seem a little passe in an age when many would rather dash off a quick DM than leave a message, but Campbell points out the market is still large - especially for small business. In NZ alone, we still record some 2 million voicemails a day.
And in case you've been wondering - yes, Turner and Campbell are a couple. "We've been living together for four years," says Campbell.
"We make a good team."