Ashton Kutcher, Hollywood actor and successful technology investor, just endorsed a photo and messaging app called Taptalk to his 16M Twitter followers on Sunday. The tweet prompted many people to wonder whether the messaging service will be Kutcher's next investment. Kutcher has had a successful career as a tech entrepreneur, with about $100 million invested in startups through his venture capital firm.

Similar to Snapchat, Taptalk sends self-destructing pictures and videos to your friends. But Taptalk has eliminated the timers and the profiles. The difference makes many of its users claim that Taptalk is an easier and cleaner interface to use than Snapchat.

With Kutcher holding a large influence on Twitter, it won't be a surprise if Taptalk attracts a substantial amount of buzz this week. It made us take a look back at some of Kutcher's most successful tech investments.

1. Foursquare and Skype
Before he co-founded his venture capital firm A-Grade Investments, Kutcher invested solo in the social network Foursquare. This investment put him on the map of the startup scene and in 2009 he invested in Skype. Microsoft bought Skype two years later for over $8 billion and Kutcher tripled his money, according to reports. 

2. Airbnb
In 2011, Ashton Kutcher invested in Airbnb through his venture capital firm A-Grade Investments. Airbnb is an online marketplace that connects travelers seeking accommodations with people renting out their homes. At the time, the startup had approximately 60,000 listings and claimed that users had booked more than a million nights through its service, according to The New York Times. In a blog post welcoming him to the team, Airbnb wrote: "With his incredible wit and personality, Ashton Kutcher has shown the world the power social media has on emerging brands and in developing strong, passionate communities. With Ashton on board, we'll be working together to take our community engagement to the next level. " Three years later, the company has over 500,000 listings and over 10 million nights booked.

3. Spotify
Kutcher also invested in the music streaming service Spotify. In an interview with CNBC's Maria Bartiromo, Kutcher stated why companies like Spotify and Airbnb succeed. "You have to have the know-how and the moxie to actually put together the pieces and build the solution in a really effective way." 

4. YPlan
In 2013, Kutcher invested in an events app founded in London. The mobile app lets users find last-minute events happening that evening and allows them to buy tickets through one click. The app, which is very popular in London, has expanded to New York and San Francisco.

5. Cryptocurrencies

Kutcher has always shown interest for technology, and investments in Bitcoin and cryptocurrencies. In fact, he's even donated $4 million USD worth of XRP to Ellen DeGeneres's wildlife charity fund in 2018.