By Small Business Chron - https://smallbusiness.chron.com/advantages-using-wifi
Wi-Fi is a method for devices such as smartphones to connect wirelessly to the Internet using radio waves. Connecting to the Internet using Wi-Fi requires a hot spot, but is always faster than the 3G cellular networks smartphones can also use to connect, and occasionally faster than 4G. Using Wi-Fi when it's available can also prove to be cheaper and make your phone run more efficiently in the long run than relying on cellular networks.
When you use a Wi-Fi network to access the Internet from your phone, the data usage does not count against your bundled data. Mobile providers often allocate a certain amount of data for free each month and charge you a fee for any data usage beyond this. By connecting via Wi-Fi wherever it is available, you can save your bundled data for situations where you might not be close to any Wi-Fi hotspots.
In many situations, your speed using a strong, dedicated Wi-Fi connection is faster than that of using your mobile network. While the difference might not be that obvious if you are only reading your email or checking out a Web page, it is very noticeable when transferring larger files. Activities such as streaming audio and video benefit from the lower latency that is associated with using a Wi-Fi hotspot. If you need to download large files or stream media to your smartphone in a hurry, it is much better to do so via Wi-Fi.
In situations where you have access to free Wi-Fi -- such as at home, work or some cafes, airports and hotels -- it makes more sense to use this method to connect your phone to the Internet. For example, if you have an uncapped Internet connection at home, you can connect your phone to the router via Wi-Fi and download all necessary updates or software without having to pay your mobile provider. There are also applications available for smartphones that enable you to make voice calls using a Wi-Fi connection; this can save you money if both you and the recipient use the app.
Battery life is extremely important for smartphones, as you will not be able to connect to the Internet or use certain functions such as the camera flash if your battery is too low. Using Wi-Fi to connect to the Internet drains less battery life than using a mobile network, especially in situations where the cellular coverage fluctuates. Since Wi-Fi is generally faster than using mobile networks, you will also not spend as much time transferring the data, which further decreases battery usage.