There are some apps which also make it possible to enable the above said service in the earlier Android versions which does not have in-built Internet Tether Software. Here are the 5 best tethering apps for such Android phones:
Barnacle Wi-Fi Tether:
This application is free to download from the Android Market and will take use of the Android Internet as a Wi-Fi hotspot. This app serves the same purpose of accessing internet on portable devices without any hassle.
This app is similar to Android Tether in some aspects. The free version supports tethering only via USB and the premium version which costs $10 also supports via Bluetooth and has lifetime upgrade facilities.
Tether for Android:
This application is way too expensive, has a cost of $30 and also has a high data transfer of 7 Mbps. This application is excellent for those people who would like to experience high speed 3G facilities.
This is an excellent Wi-Fi tethering app which will cost about $25 and is completely easy to use. The unique internet tethering ability will allow to access internet for laptops and notebooks. The free version has limited yet useful features:
This app enables both wifi AND bluetooth-tethering for "rooted" handsets. The app is completely free to download.
All the apps mentioned above are FREE to download and free version is enough to access internet most of the times unless and untill you need extra features.