Direct answer
Pre-launch failure is checkout-disabled optimization: owners polish themes while payments stay untested. Ship plan plus PSP in day 1, cap at ten SKUs with real photos, pass thumb-only mobile checkout, then one analytics plus email capture flow.
Launch metric: one paid test order end-to-end beats perfect branding with zero transactions.
| # | Tool | Starting price | Rating | Action |
|---|---|---|---|---|
| 1 | Shopify | $5/mo | 4.6/5(4,800) | Try Shopify |
| 2 | Klaviyo | Free | 4.6/5(9,100) | Try Klaviyo |
Basic is enough for most launches. Connect Shopify Payments or your PSP. Place one test order end-to-end.
Ten products with real photos beats 200 with AI filler. Shipping rules and tax zones only for countries you ship to.
Complete purchase on your phone with thumb only. If checkout takes >60 seconds, fix before ads.
Enable Shopify analytics. One welcome flow or abandoned-cart email — not five apps yet.