With this question, I tried remembering the most used products of my month, but since they usually keep on changing based on my requirements I tried thinking deeper about products that I wonder how I would have survived without them. One of the top most is Google Maps.
The first time I stayed alone in a city, Kolkata, was in 2015 where I was due for taking entrance tests. Since the nearest city from my place could only be accessed by flights, I decided to stay longer. To cut down on travel costs, I chose to take local buses and trains but I needed to know the exact paths, the availibility of public vehicles on the stations or stops, the type of area around(ref. safety), the time taken to reach with multiple vehicle changes in between, etc.
Without an available carrying smartphone or internet connection, I needed to ask strangers around my place of stay about certain locations and possible mode of transports, and while few places were known, few were not. That made me start few hours earlier or sometimes check out the centre the previous day(if within the same district), while iterating paths through traffic police, strangers, bus conductors, etc.
And today, all of these needs are fulfilled by GMaps available features. It made me go around independently and get things done, without the need to wait for or depend on uncorrelated information, from house hunting to traveling to finding nearest necessity to shifting cities.
A slight example of house hunting or travelling(finding accommodation): I use NoBroker(maps integrated), Facebook listing, Booking.com(travel acc., has maps integrated). Since I do not ride a personal vehicle, I travel by public transport vehicles or walk for max. of one kms., and thus, I need to find the availibility of transport in certain junctions or roads, and what could take the lowest time but most feasible to go to a place e.g. office from home., if there are available places for everyday essentials nearby, how much time it shall take for me to reach an event at a new location/office, etc.