Just wanted to clear things up... If you are pertaining to the pocket wifi modem called "4G pocket wifi" (price is less than Php 2,000) then the 4G indicated there is just for marketing purposes (they considered HSPA+ which is actually 3G as 4G) and it will just cater to 3G and 2G signals.
Now if you see that LTE is indicated in the wifi modem (price is above Php 3,500) then it will also be compatible to 3g or even 2g if LTE is not available in your area.
There is a lot of misinformation going around for the sake of marketing and how we wish that they could only stick to the truth.
Thanks Chito this is very helpful! I agree with you, this is not fair that they market this as 4G but actually it's 3G. This is unfair trading!