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Craig Cathcart put the visitors ahead before substitute Simon Church won and scored an 89th-minute penalty.
"There were lots of positives out of it even if we'd have come off and lost 1-0. They had a good mentality and attitude," said Coleman.
Wales face another Euro 2016 warm-up game against Ukraine in Kiev on Monday.
"We look forward to our next challenge now," added Coleman.
"The team will change up again, and we'll see how they go again."
Striker Church, currently on loan at Scottish Premiership side Aberdeen from Reading, was delighted with his equaliser from the spot.
"Northern Ireland were a tough side to play against. They've obviously done well to get where they are and it was a tough game," he said.
"We wanted to do well because it was the last time a Wales crowd would see us before the Euros and we wanted to put in a good performance.
"I've just got to keep going now and hopefully score some goals. This is a great squad to be part of."
Wales manager Chris Coleman said he was pleased with his team's performance after they came from behind to draw 1-1 with Northern Ireland in Cardiff.