Backpacks leave your arms and hands free and shift the weight to your back. This makes them a great choice for heavier babies and toddlers.
Unlike front packs and slings, however, backpacks do not provide substantial eye-to-eye or skin-to-skin contact. Instead, most backpacks are designed for active parents interested in longer day trips or hikes.
Since backpacks are relatively expensive, it pays to do some research. Although they can be purchased online, it is best to try one on at a store. Walk around carrying your baby for ten or fifteen minutes to see if it is comfortable and baby is amenable.