Finding your bearings in Brazil

GPS is a wonderful piece of technology, but in Brazil it is one that must be monitored and checked to ensure that it doesn't take you somewhere you don't want to go.  I have a TomTom GO620 and keep it up to date.  I've used it traveling between Recife and Natal.  Used it in Joao Pessoa, and extensively in Natal.  There are a number of things that cause GPS here in Brazil to be only a tool to be used and not relied upon religiously.  Traffic patterns in major cities change often and 2-way streets become only one way and many intersection it is forbidden to turn left.  Other issues are the way that the government changes address of long standing building which throws off target locations by several blocks.  But the next parallel block will have the correct number address.  For example the target address maybe 1701 but the government changed the addresses so 1701 is actually located 2 or 3 blocks away on that particular street.  Meanwhile the parallel block will correctly show the 1700 block to be where it should be!  Other issues, they change the name of streets.   Did anyone change the numbers on the outside of the building from the old to the new numeric address..........Noooo!   The other day I couldn't get the TomTom to re-route my destination plan and it kept trying to bring me back to the same street that just changed to a one-way street going in the opposite direction.  We flipped to Google on the cell  phone.....same problem!   I would not leave home without the TomTom.....but ya got to watch what is happening and learn how to make adjustments that you won't find on Google or TomTom!

In cities, GPS-based apps like Google Maps are a godsend, even with the shortcomings Gotcha184 mentions.  I find that I often know street names better than my Brazilian in-laws, from studying the maps on the apps.  Since flashing your cellphone around on the street is a bad idea, though, for a walker like me navigation is more a matter of plan the route and memorize it ahead of time, rather than checking the screen a lot in real time.
Here in Manaus, where foreign tourists make up an important element of the local economy, it's relatively easy to find the principal tourist attractions by following the multilingual signage.  For anything else, though, the signs are pretty useless.  Even many of the street signs have been bleached out by the strong equatorial sun, and are seldom replaced.
I've always found people I've asked for directions to be friendly and helpful, wherever I've been in Brazil.
One thing I miss from pre-GPS days is street maps.  It used to be possible to get a street map of just about any major Brazilian city at a bookstore.  Getting one was the first thing I did when I visited a new city, and I would study it to learn the neighborhoods where I'd be spending my time.  Google Maps and Waze are strong in helping you get from Point A to Point B, but not nearly as good as an old-fashioned paper street map in helping you understand how your route relates to the larger city, and how the various neighborhoods relate to each other.