We are planning a first time visit to the Grand Canyon. Our travel route takes us closer to the North than the South Rim so it would definately be more convenient to visit the Northern part.Will we be missing out on something by not going to the South Rim?
Our trip is at the end of April.Will the North Rim be accessible ?

The North Rim of the Grand Canyon does not open until May, most years. The road south from Jacob Lake is often choked with snow. Advise that you check the National Park Service web site as your time of departure draws near.

Definitely go to the North Rim if it's open. Less touristy and less crowded. We much prefer. Are you missing anything? Only the crowds!

The North Rim might not be accessible at the end of April, as Al and others suggest. You will have to ask. I am headed there, but we scheduled the North Rim for late May.
As for the two sides, the South Rim draws the mobs. But, I think you can see into the canyon better from the south. There are more overlooks and the angle of view is slightly different. The canyon is cut into the side of a hill, so that the North Rim is about 1,000 feet on average higher than the South Rim. (That is another reason for the heavier snow fall and cooler climate.) But the solitude, relatively speaking, of the North Rim is welcome after mob city. The ponderosa pine forest that you drive through to reach the North Rim is beautiful.

Bob, you said it much better than I did earlier as to why the North Rim is preferable. And, yes, that drive (about 40 miles) through the ponderosa pines is indeed beautiful!

One other thing: the number of facilities available in the North Rim are much fewer than the South Rim, a reflection (or a cause?) of the much smaller crowds there. If you want choices in where you stay or dine, you won't find it at the North. For me, that's fine; for others, it's a problem.

Travel to the South Rim was first promoted by the Santa Fe Railway (actually, the Atchison, Topeka and Santa Fe Railway Company)which built a spur line connecting Williams, AZ on the main line of the railway with the South Rim around 1900. The El Tovar Hotel soon followed, with cabins, a Fred Harvey dining room, etc., etc. Then it was named a National Park by Teddy Roosevelt, and the rush was on. The railway brought tourists to the South Rim long before a paved road ever existed. Then the town of Tusayan, at the gate to the South Rim, mushroomed into the motel-and-watering-hole spot it is. Today, a private company operates that same spur line--it's a great experience for thousands of tourists each year. On the North Rim, no rail service has ever existed as far as we know.

Another consideration about choosing which rim. I don't think crowds will be much of a problem in April. We went last June,and they were bearable. What kind of hiking or walking do you want to do? Granted the North Rim is more remote, feels closer to nature, and less impacted by civilization. But unless you are a sturdy hiker and able to hike down the canyon and back up, the South Rim affords a little more opportunity. You can take easy rim hikes/walks for a few miles on the south side. The tram takes you along the rim, if walking is tough, eliminating traffic congestion. And there is a little more "entertainment". When we visited last year, the astronomical society was there, complete with over 100 hundred telescope to share with visitors who wanted to view the night sky. Native American performers dance occasionally, and there are more activities if you have kids.