One of the things for many people that travel internationally is that for the most part, US wireless carriers don't include free international roaming. When they do, it's often costly and complex to setup. The alternative is to buy a sim when you get there, but Keepgo is another option. They offered me a choice of a 4G LTE data sim or 4G LTE mobile WIFI hotspot that works in more than 120 countries. We tested it out on our trip to Loreto, Mexico and frankly the results were mixed.
The concept here is simple. Instead of buying a sim in the airport and trying to set it up while you are in a foreign country, simply order Keepgo online, set it up at home, and then it manages the connection whether you are in Mexico or Germany. There's no need to buy multiple sim cars for each region you travel. Keepgo offers free shipping for the sim to more than 200 countries and 39 countries for the hotspot. Prices start at $49 for the sim and $99 for the hotspot, including 1GB of data that does not expire. You can refill your data allotment with various plan levels ranging from 500MB for $14 to 10GB for $165 by visiting their website and picking which option best matches your needs.
I chose to go with the 4G LTE Mobile Hotspot since that was ultimately easier for me than having to worry about switching out my sim card. (NOTE - many phones, such as my Huawei phone, do support multiple sim cars so that this is not an issue.) My thinking was that having the WIFI Hotspot available would not only allow me to access the internet on my phone but also tablet and laptop as well. In fact, it does just that. However, the interface on the Huawei-made hotspot device is somewhat challenging to configure and one of my associates accidentally used about 300MB of data at home during setup, because he didn't realize it was still active.
Unfortunately, what I discovered while traveling to Mexico is that while the map showed coverage - it wouldn't connect for us. We had a similar situation a week later while traveling in Maryland as well. I'm not sure why this is and ultimately I know that the system works since it connected with no problem in San Diego. However, based on this experience I'd have to say that like anything involving mobile carriers - your mileage may vary. I suspect that Keepgo will be a great option if you were traveling to major cities but perhaps the carrier arrangements aren't at the same level in less populated areas - even though roaming with Verizon or T-Mobile has no trouble negotiating the connections.