This is simply not true.

It is correct, that US phones sometimes use another frequency for their data as European phones, but this is mostly a problem the other way round (i.e. I need a UMTS Pentaband mobile to make use of the 4G network of T-Mobile in the US). As far as I know, this is not the case if using Verizon phones.

The big companies T-Mobile and Vodafone have a very good coverage and like put by other in 99% of the urban areas your are covered by 4G, in some suburban regions only 3G is available and in very few countryside location you have only basic internet service.

O2 has also a good coverage.

I am not absouletely sure where ToGo lives / travels, but you only run into this problems if you spend most of the time in a rural area far away from any major city (i.e. Mountains, parts of Schwarzwald, area around "Brocken", ...)

The last time i was in Berlin i try to use VoIP on my Cellphone in the Subway and SBahn in Berlin and the Connection often drops or when i try to connect in a Berlin Hotel the connection was very slow.
When i am Home i can watch TV in the Subway and make VoIP Call over hours w/o the connection drops....

Smart phone options while in Germany?
 

ToGo - you didn't mention what carrier you were using and speed. It's not useful to make a blanket statement that coverage in Germany is bad if your only data point is Berlin and not specify the carrier/speed/equipment you were using.

I made VoIP calls using FaceTime and Vonape app without problem on 3G in Duusseldorf. Couldn't get a signal in the countryside.

Basing your comments on that experience is silly. It's possible that back in Asia your city may be more advanced in its cell service buildout, but I don't think anyone has a reasonable expectation to have reliable service in underground tunnels in most cities.

The S-Bahn mostly runs above ground. However, part of the S1/S2 lines run in a tunnel through Mitte where the signal does drop out (usually between the Anhalter Bahnhof and Nordbahnfof stations). But I usually get pretty good reception in the U-Bahn. Mainly because they are really not deep tunnels. In fact, their "ceiling" is basically the road above it.

Simyo, Blau and Aldi do offer LTE.

http://www.lte-anbieter.info/prepaid...e-ratgeber.php

Thanks. I have blau and will take a look next time I'm in Germany.