Landing in Tallinn with an Estonia eSIM means you walk off the plane, your phone finds Telia or Elisa, and you open Bolt or Pilet.ee without hunting for a kiosk. Installation happens before you board — scan the QR code esima emails you, confirm the new data plan in Settings, done.
The eSIM activates when your phone sees an Estonian tower, so there is no counter visit, no passport photocopy, no cash deposit. Estonia's three carriers — Telia, Elisa, Tele2 — all peer with each other's infrastructure, so handoff between networks is smooth as you move between Tallinn's port district and Tartu's Toomemägi hill.
The practical difference between this and a physical SIM from an R-Kiosk is zero once you are connected; the advantage is you keep your home number live for two-factor SMS while the eSIM handles data.
Hotspot works out of the box, so you can tether a laptop in a Tallinn café or share signal with a travel partner on Saaremaa.
The country is small — Tallinn to Tartu is ninety minutes, Tallinn to Pärnu is two hours — and the E263 highway has unbroken 5G from Telia for most of that drive. Lahemaa's coastal villages (Käsmu, Altja) have 4G, but the interior bogs thin out to 3G or nothing; Elisa has the best penetration there.
ParkiMobile and Pilet.ee are the two apps you will use daily, and both require live data at the moment of transaction — paper tickets and coin meters are nearly extinct.