As of 2014, there are three major carriers that offer mobile connectivity for tourists, with T-mobile having the best coverage, followed by Vodafone and o2. A passport is required to purchase and register your SIM card.
Top Prepaid SIM options
1. T-Mobile (Telekom Deutschland)
Cost: Sims are ($13 USD) with credit, ($3.75 USD) for unlimited data lasting one day, or ($19 USD) for unlimited data lasting one month. Link
2. Vodafone
Cost: Sims are ($6.30 USD), ($6.30 USD) for 200 mb data lasting one month, or ($19 USD) for 1 gb data lasting one month. Link
2. O2 (and e-plus)
Cost: Sims are Free, $10.17 USD for 250 mb data lasting one month, or $25.45 USD for 1 gb data lasting one month. Link
Where to Buy: Authorized outlet.
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