FlowPost: Flow Email via SMTP vs RenderKu: Email Templates
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Oct 15, 2026 for FlowPost, Oct 18, 2026 for RenderKu.
The short answer
- Both list a free plan. Paid plans start at $9.99/month for FlowPost and $12/month for RenderKu.
- RenderKu lists 14 features FlowPost’s listing doesn’t mention, including Abandoned cart, Back-in-stock emails, Browse abandonment.
Head to head
Momentum
New reviews each month
Review pace is the clearest public read on how fast an app is winning new merchants.
Free
- · 1 email provider
- · 7-day log
- · 75 emails/month
Starter
- · 1,000 emails/month
- · All providers
- · Attachments
- · Backup provider fallback
- · Delivery status
Growth
- · 3,000 emails/month
- · 90-day log
- · Multiple senders
- · Priority queue
Scale
- · 180-day log
- · Priority support
- · Unlimited emails
Free
- · Access to free stock photos, graphics
- · Unlimited exports
- · Up to 2 emails
Pro
- · Unlimited emails
Plus
- · 3 users included in plan
- · Add multiple users to account
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureShopify Flow's built-in email can't send to a customer's address. FlowPost adds a Send transactional email action to Flow, so you can email customers, staff or suppliers when anything happens: order tagged, COD order, B2B approval, low stock or fraud risk. Send from your own domain through SMTP, Gmail, Microsoft 365, Amazon SES, Resend, SendGrid, Mailgun or Postmark.
RenderKu helps you create Shopify email templates without accessing or modifying your store data. It works entirely with Shopify liquid variables and requires zero access scopes. By design, it cannot modify your products, collections, orders, or any store data. Use the drag-and-drop editor to design templates ready to export and use in Shopify notifications.
- Send transactional email from Shopify Flow workflows
- Connect SMTP or providers like SES, Resend, SendGrid, and Mailgun
- Optional fallback routing when the primary provider fails
- Templates and sent-email logs for day-to-day operations
- Level up default email notifications with visually appealing email templates
- Drag and drop editor to make quick changes to email templates.
- Liquid templating compatible. Support adding liquid code into RenderKu's editor.
- Newsletter templates available for your email marketing campaigns.
All the numbers
Every figure, side by side
A green dot marks the app ahead on a measured figure. Estimates, gaps and apps that leave no storefront trace never take the lead.
Adoption
| Measure |  FlowPost |  RenderKu |
|---|---|---|
| Detected stores | Not published | Not published |
| Net store change, 28 days | 0 | 0 |
| Stores added, 28 days | Not enough data | Not enough data |
| Big-brand share | Not enough data | Not enough data |
| Top store categories | Not published | Not published |
| Top store countries | Not published | Not published |
Reviews
| Measure | FlowPost | RenderKu |
|---|---|---|
| App Store rating | Not published | 5.0 ★ |
| App Store reviews | Not published | 10 |
| New reviews, 28 days | Not enough data | 0 |
| Reviewers a year or more in | Not enough data | Not enough data |
FAQ
FlowPost and RenderKu: common questions
- Is FlowPost or RenderKu cheaper?
- Both list a free plan. Paid plans start at $9.99/month for FlowPost and $12/month for RenderKu. Shoplist compares base prices only between monthly plans in the same currency; usage charges and annual plans vary, so check each plan’s limits.
- What features does each app list that the other doesn’t?
- FlowPost lists 6 the others don’t mention, such as APIs and webhooks, Automations, Custom campaigns, Email domains. RenderKu lists 14 the others don’t mention, such as Abandoned cart, Back-in-stock emails, Browse abandonment, Cross-sell emails. A feature missing from a listing may still be supported; this compares what each App Store listing says.
- Where does this comparison’s data come from?
- Shoplist crawls Shopify storefronts to detect which apps each store runs, and reads each app’s Shopify App Store listing for reviews, pricing, features and integrations. Store counts are as of Oct 15, 2026 for FlowPost, Oct 18, 2026 for RenderKu; estimated figures are labeled.
How Shoplist compares apps
Store counts come from Shoplist’s crawl of Shopify storefronts, which detects the apps each store runs; they are as of Oct 15, 2026 for FlowPost, Oct 18, 2026 for RenderKu. Reviews, ratings, plans, features and integrations come from each app’s Shopify App Store listing. 28-day figures are labeled when estimated, and a figure that is missing or estimated never decides who leads. Read the methodology.