This is my go to place for bubble tea. They have a huge selection of flavors, and you can even choose between different bubble types.
I personally like my tea without ice, with mixed tapioca bubbles, and at half-sweet (the standard sweetness for bubble tea almost everywhere I have found too sweet).
While this place is lovely to sit with friends, and they also serve full meals, I would not recommend it as a work or study place because the wifi is somewhat inconsistent.