Computer app for directions in Paris

Google Maps. And if you don't want to use your data, you can download the maps and use them offline.

Citymapper.
It was recommended by several people who live in Paris and post here.

I'm with Bets. I took Kim's advice and downloaded Citymapper. I had data so don't know about offline maps. It was terrific either walking or metro.

Thank you, really appreciate it.

Organic maps is the best app for walking directions and also gives metro directions. The maps are much more detailed, accurate and up to date than Google maps, as well as being a lot more legible

Citymapper is great because if you are connected, it will give you real time info regarding traffic delays, road closures, metro train arrivals and departures, alternate transportation, etc.

Google maps - for walking in Paris

Citimapper - for information about public transportation

RATP Mobilite - for those wanting to use their Samsung phone rather than a Navigo Decouverte or Navigo Easy card.

I used HereWego app this past January and was really impressed with how well it worked. https://www.here.com/applications/wego

Download the free Paris by metro map. You can enter any metro station starting point and it will tell you how to get to the metro for your destination. Makes it possible to find you way home. Google maps works well for walking directions but you have to be careful. It isn't perfect. You can stay out of trouble if you take some time to study landmarks or try to get a sense of direction like the direction to the Seine or something like the Montparnesse or Eiffel tower.

CityMapper, for sure.

CityMapper! The best part is how it tells you where to sit on the Metro and which exit from the station to take. Comes in clutch in cold/rainy Paris weather.

The OP has completed their trip.