MOBILE PHONES: Telephone service for mobile telephones is provided by many competing companies, and each has differing coverage areas. The cities and major highways usually have good service, but less traveled routes and most birding hot spots are spotty with weak, intermittent, or no service. The most useful communication app is WhatsApp. Walmart offer some non-contract (top up) mobile telephones for good prices. Sym cards are not available for non-U.S. mobile phones.
WIRELESS INTERNET: Most hotels offer free wireless internet, but sometimes with a weak and slow connection. McDonalds and some other restaurants offer free internet.
MAPPING: Maps on smartphones are good when there is service. It is advisable to print or save on the device maps of remote areas ahead of time (as without reliable wireless internet and without reliable telephone service maps may not be available for remote areas). Satellite navigation devices work virtually everywhere and are reliable. It is usually less costly to purchase a satnav device rather than rent it for an extended period. Most birding hot spots have printed trail maps available and there are some books published with trail maps (such as ABA Birder Guides, Dave Gosney guides).