The History of Trunks
Future Tien's life was exactly the same as his main timeline counterpart's life until the Trunks Saga. In August of Age 764, Tien watches as Future Goku uses the Instant Transmission to arrive on Earth and kills Future Frieza and Future King Cold (something Future Trunks' arrival in the main timeline alters). Two years later, in Age 766, Goku dies from a lethal Heart Virus, and is unable to be wished back due to the death being of natural cause. Tien is shown outside Goku's House when Goku dies.
On the 12th of May, Age 767, two killer androids appear. Coming to the defense of Earth's inhabitants, Future Tien and the other Z Fighters engage the androids in battle. Future Tien is the fourth Z Fighter killed by the androids; he dies after Yamcha and before Krillin and because of Piccolo's death, the Dragon Balls vanish permanently as the Z Fighters are unable to be wished back, which also kills Kami.
In the TV special prologue, Future Tien is shown in receiving a swift punch to the stomach by Future Android 18, and in Future Trunks' flashback in "Ghosts from Tomorrow", it is shown that 18 killed him by blasting a hole through his chest with her High-Pressure Energy Wave. The only survivor of the battle is Future Gohan, who dedicates his life to avenging his fallen friends.
Future Tien was 34 years old when he was killed by the androids.
Dragon Ball Super
In a flashback in "Extra Edition 1" bonus chapter of the Dragon Ball Super manga, Future Tien Shinhan is shown fighting the Androids alongside his allies.
"Future" Trunks Saga
Main article: "Future" Trunks Saga Future Tien Shinhan's spirit was erased when Future Zeno wiped out all existence to end Infinite Zamasu's reign of terror. His spirit still continues to exist in the new timeline Whis (in the anime) created or by Future Trunks and Future Mai (in the manga).