The Android client I've been using for more than 5 years with great success is "Dynamic DNS client" by Neil Boyd (search Google Play Apps for "org.l6n.dyndns", and DO put the double-quotes around it). Usual Disclaimer: I'm not in any way affiliated with the app -- just a very satisfied user.
Actually, there are valid reasons for using a dynamic DNS updater client on an Android mobile device.
And, no, having my phone's IP address kept current as I roam about on various networks does NOT "claim someone else's network address as your own" in any way.
Nor does it have ANY effect on my home network, which uses a different OpenDNS host name ("home.domain.com" versus "phone.domain.com", for example).
To assert that when you change your dynamic DNS address you will "leave your home network unrpotected by OpenDNS" simply means that you don't understand the product you're using. Setting your home (and/or mobile) clients to use OpenDNS as that device's (or network's) DNS service provider is where you derive "protection".
That is completely separate from, and unaffected by, dynamic DNS, in which a fixed "name" (such as "martha-iphone-5@opendns.com") maps to whatever her phone has managed to connect to (allowing for the few moments between a new address being assigned, and the dynamic DNS updater client detecting, and reporting, the change).
Whether the latter functionality is useful to you depends on what you're trying to accomplish.
For me, it's making my Android phone (and laptop, and tablet, and ...) reachable on the Internet as if it were a web site server. For my purposes, that is precisely what I need dynamic DNS to do for me. This is not a typical need for most people. But when I need to allow others to retrieve a file from my phone, or download a batch of photo samples from my laptop while I'm in a taxi, dynamic DNS is exactly what I need.
--tgi
