As big companies besides Samsung seem to have abandon the rugged smartphone market, Chinese manufacturers take advantage of the situation and fill the gap in the market. One of these manufacturers are ZOJI Z6 and Z7 that offer decent features for below $100 price tag.
The ZOJI Z6 is a 4.7″ display rugged smartphone with minimum acceptable specs. That means that it sports the MT6580 SoC accompanied by 1GB of RAM and 8GB of internal storage. Its killer features are the 3000mAh battery capacity and IP68 certification. It sells for $62.99 and you can find it here.
On the other hand, the ZOJI Z7 features more adequate specs with MT6737 SoC and 2GB of RAM as well as 16GB of storage. Its display is a 5″ HD one and the battery has 3000mAh capacity as well. Of course, IP68 certification is present here too. You can find it here for $80.99.