This is very useful--worth mentioning here. The below app is *highly* recommendable:
"FoxFi (WiFi Tether w/o Root)"
It is a free app you can use on most newer cell phones with Android OS. Quite simply it enables you to create your own network, your own Internet access, your own WiFi HotSpot without paying your phone company for an additional plan for Internet access. That means your cell phone functions as a modem. That allows your cell phone to connect to the Internet (for emails, web browsing etc.), but that also means you can--within maybe 15 or 20 seconds--turn your cell phone into a modem to then use your laptop, netbook, iPad tablet, or another cell phone to go online. The ONLY thing to watch for is to inform yourself what kind of cell phone plan you have, how much data transfer your plan includes. Other than at your home with a landline connection this will likely be limited to a lesser amount (all depends on the country you live in and the company and plan you have signed up with). So, when using your cell phone as WiFi HotSpot you possibly may NOT want to watch movies online, and just do "normal" Web browsing and emailing (your phone company may otherwise charge you for going over the max. with data transfer).
The app can be downloaded from within your cell phone via the Google Play application/interface, shows as "Play Store" on my phone. Just search for "FoxFi" in there--but the full name is: FoxFi (WiFi Tether w/o Root)
You can read more about it at:
(especially the user reviews)
It is extremely simple to use!
After installation, just touch the "FoxFi" app icon, and then click the "activate WiFi Hotspot" option and wait 15 or 20 seconds. That same screen then also presents you with a "Network Name" (e.g. 'FoxFi35') that your other devices such as your laptop will then detect as an available router under that name. Note that you can also set a password right there on that same screen.
LAST NOTE: "FoxFi" can create a WiFi Hotspot but also works with Bluetooth. Not all of the devices you may want to use, e.g. not all iPads (I believe) have Bluetooth. So using WiFi is better. However, in case you use the new Samsung Galaxy s3, you may then NOT upgrade the present Android 4.04 to the 4.1 version (known as "Jelly Beans") as this will not work with the app discussed here ... for Bluetooth yes, for WiFi Hotspot no. So you may want to disable auto-upgrades of the OS on your cell phone until "FoxFi" is upgraded to work with Jelly Beans.