ATMs are widespread in most midsize towns in Nicaragua, but you'll need to stock up on cash before heading to rural areas. Credit cards are widely accepted in larger towns but rarely in rural areas apart from higher-end hotels. US dollars are the alternative currency and widely accepted, but for smaller items using córdobas is cheaper and easier.
It's worth carrying an emergency supply of dollars in case you have problems with your card.
Tipping is not widespread in Nicaragua except with guides and at restaurants.
Guides Tipping guides is recommended as this often makes up the lion's share of their salary.
Restaurants A tip of around 10% is expected for table service. Some high-end restaurants automatically add this to the bill. Small and/or rural eateries may not include the tip, so leave behind a few coins.