For potted plants, a fully coated, slow-release fertilizer is better than quick release. Among those, Calibercote and Nutricote and a couple of others, tend to be more expensive, and better too, than Osmocote.
With careful, sparing, monthly use, an inexpensive quick-release fruit-tree fertilizer, such as the Rare Fruit Council's 8-3-16, or Excalibur's 8-3-9, work quite well in containers.
Palm fertilizers work well for most fruit trees in the ground, but often harm potted plants. I use Helena 8-2-12 a lot around trees in the ground, but I have hurt potted ones with it.