Never heard of Jesse Underhill? That’s OK, the Jewish-American TikTok star has never heard of you, either.But if you have teens or tweens, you may be aware of this phenomenon, who will be appearing with popular Israeli TikTok performers at the TikTok Live show on December 29 at the Menora Mivtachim Hall in Tel Aviv. Tickets to the show are selling fast and they run from NIS 99-149, which may be a lot of money for teens but a lot less than you’ll have to shell out to see older dudes, like Lionel Richie, who will be playing the same venue in March. Underhill will be appearing with more than 20 Israeli TikTok stars, including Noa Bog and the Formula Band. The tickets are almost sold out and have been selling faster than organizers anticipated.Underhill, who has more than five million TikTok followers, posts music videos and clips of himself singing, lip syncing, dancing and chatting. He can also be seen on such platforms as YouTube, Snapchat and Instagram. But his real fan base is on TikTok, the app known for very short videos and which is intended for mobile phone use.Excitement is running high, especially among the teens and tweens who are his biggest fans.Shira Rosenberg, an 11-year-old Jerusalemite, said she likes Underhill “because he has original content. He’s funnier than the others. He’s a really good dancer. I like his style. You see what’s on trends and he’s better than they are.”Adi, another Jerusalem tween, said, “He’s coming to Israel and he wants to speak Hebrew. Most of the kids really like him here, and also abroad. He’s really handsome and everyone wants to see him.”Tamar, a 12-year-old who lives in Tel Aviv, said she would like to see him, but she is so young that her parents would have to bring her and they won’t be able to. “I hope he comes back when I am old enough to go by myself.” Like some of the other fans I spoke to, she struggled to articulate exactly what she liked about him. “His clips are just the best on TikTok. Everyone thinks so.”In a video posted to YouTube, Underhill, who sports an orange-y bleached blond pompadour, says that he finds it challenging to use Twitter and that his pet peeve in relationships is girls who don’t text him back quickly.But that’s likely to be a rare problem for Underhill, who has inspired over 50 fan accounts on Instagram – for comparison, that’s about as many as long-established stars like Jennifer Aniston and Natalie Portman have.TikTok was originally available as musical.ly in the US but was rebranded in 2018. It has hundreds of millions of users and is meant only for those over 13. Concerns have been raised over children’s privacy and the app. Earlier this month, TikTok’s parent company paid $1.1 million to settle a US lawsuit that accused it of violating child privacy laws by selling minors’ personal data. On December 20, the US Navy banned TikTok from government-issued mobile devices, saying the app presented a cybersecurity threat.Cybersecurity threat or not, admirers continue to tune into him on TikTok.