A 4G LTE modem-router dongle  when paired with a high-end unlimited-hotspot phone plan like Digi Infinite 150 and TM UF Bebas Weekly/Monthly, allows the subscriber to  do their online stuffs with a computer, instead of the limited handphone, eg serious office work, video-editing, CAD, CGI movie-making, website development, etc. Some people prefer or need computers for their online activities and work.

Note that it is illegal for phone plan subscribers to use modded 4G LTE modems or the PdaNet+ app to bypass the monthly hotspot-data limit = if detected by the celcos = suspended, terminated, blacklisted or CTOS.

.
PS - High-end 4G LTE modem-routers(> RM500) even has a RJ11 connection for the home push-button telephone which uses the mobile number of the SIM card for voice calls.
.