A specific pain when you are replacing Stocky and shopping PO apps: a lot of them build a purchase order off your whole catalog. You end up scrolling every product to pull out the handful from one vendor. If you buy from more than a couple of suppliers, that is the difference between a two-minute PO and a twenty-minute one.
What you want is supplier-first, not catalog-first. You assign each product to the supplier you buy it from, and when it is time to order you pick the supplier and the app shows only their items, already flagged for what is low. That is the workflow Stocky's PO section got right, and it is why so many stores are struggling to replace it.
The pieces that make it work: products linked to a supplier (a SKU can have more than one if you dual-source), a per-supplier reorder view with suggested quantities from recent velocity, lead time per supplier so the timing is right, and real receiving for partials and over-shipments. You do not need an enterprise tool for this, the supplier-scoped workflow is table stakes, and several apps (including free tiers) do it. What to test in a trial is whether creating a PO starts from "pick a supplier" or whether you are still filtering a full-catalog list by hand.
For those who have moved off Stocky, how many suppliers are you ordering from, and did the app you picked actually let you build POs per supplier, or did you end up back in a spreadsheet?
7 suppliers. Supplier-first or nothing, a catalog-first builder is unusable at that count.
Add dual-sourcing to your list. 2 of my SKUs come from different vendors depending on price that month.
Loads of apps assume one supplier per product and just break.