Kissing: no need to kiss strangers, but in social settings a single kiss on the right cheek will do.
 
“No Hay”: a “jazz hands” wave with the right hand isn’t a hello – it means “no hay,” – there isn’t any – whether that’s another seat on the bus, food in the kitchen or chips in the corner store.
 
Come Here: speaking of hands, when waving someone over, keep your palm toward your body and your fingertips pointing toward the ground.   For Americans this may feel a bit like the way one calls a pet, but rest assured, it is the way to call someone over in Ecuador.
 
Taxis: while the use of meters is obligatory in Quito and Cuenca, drivers consider $1 ($1.39 in Cuenca) to be the minimum fare no matter what the meter says.   In other places negotiate the fare before getting in.   Tipping is not customary, although you may be lead to believe otherwise if you’re an obvious foreigner. Taxis are supposed to use 'Taxi Metro' -- their meter -- during the day; the fare will be pretty cheap. At night they can charge more.  In Cuenca the nighttime fare is an additional 50 cents.  Many taxi drivers will charge foreigners much more than they would charge locals, so be sure to agree on a fare before getting into the taxi. Once an agreement is reached, they tend to honor it. From Quitumbe (the southern bus station), taxis are likely to charge a fixed rate, perhaps $8 for a ride to Old Town, and $12 to the airport. A higher fee is probably not necessary
 
Restaurants:   mid-level to upscale restaurants will tack a 10% service charge onto your bill (along with a 12% tax).   No need to add anything on top, unless the service has been exceptionally stellar – and in that case a dollar or two to indicate your appreciation would be fine.   Economical establishments do not usually include either tax or a service charge, and rounding up would be appropriate.
 
Hotels:   fifty cents per bag is plenty.
 

And while the tips below may not come up for tourists, they can come in handy for those who are moving to Ecuador:

 
Bag boys at the grocery store – 25 cents to a dollar is fine, depending on how many groceries they tote to your car and how generous you feel in the moment.
 
Gas station attendants – no tipping, unless they check the air in your tires – then a buck or so is fine.
 
When talking to (male) strangers, “joven” is a suitable way to address a youth (rather than muchacho), “maestro” for laborers such as carpenters, and of course “señor” is virtually infallible for all situations. 

"Extranjeros" is the Spanish language term for foreigners, and "Gringos" is the term used for English speaking North Americans.  "Jubilados" refers to those in retirement.