A shop or online store collects hundreds of customer numbers over a year - at the till, on delivery notes, in a WhatsApp catalogue. Most of that list just sits in someone’s phone. The customers who already bought once are the cheapest to sell to again, but only if you can reach them with the right message and actually know it landed.
Where repeat sales go to die
- Contacts are scattered across staff phones and old notebooks
- Blasting the whole list annoys people and burns money on the wrong audience
- WhatsApp broadcast lists cap out and give no record of who received anything
- You find out a “cheap” SMS was actually charged as three because a smart quote pushed it into Unicode
One list, grouped the way you sell
Every customer lives in one shared directory - SMS number and WhatsApp number tracked separately, because they’re often different. Bring contacts in by CSV (with column mapping and duplicate detection), from your invoicing customers, or via the API. Then build saved segments: recent buyers, a specific product’s customers, a town or an estate - and message exactly that group instead of everyone.
Send SMS and WhatsApp that land
Write once, personalise per person. Save a template with {{name}} and other placeholders - Zana fills each recipient’s name, and your campaign values (offer, code, link) fill the rest. WhatsApp campaigns use Meta-approved templates; SMS just needs a body.
Know the cost before you send. SMS is billed per segment, and Zana counts segments accurately - 160 characters for a standard GSM-7 message, fewer if you use special characters - and even transliterates smart quotes, dashes, and non-breaking spaces pasted from Word so your message doesn’t silently become a costly multi-part Unicode SMS. You see the estimated cost, the audience size, and how many are opted out, before you commit.
Worked example. A hardware store texts 800 past customers about a cement promo. The message is one GSM-7 segment at KES 1.00, so the run costs about KES 800 - shown up front. Forty numbers on the opt-out list are dropped automatically. After sending, 771 show delivered, 12 failed (wrong numbers), and the store exports the list to clean its data.
See exactly what happened, per person
Every recipient has a live status through eight stages - queued, sending, sent, delivered, read, or failed/skipped/opted-out - with separate timestamps for sent, delivered, and read, the provider message ID, and a machine error code if it failed. A late “sent” callback can never overwrite a “read”. Export the whole thing to CSV as literal proof of send. Per-campaign analytics give you delivery rate, read rate, and a failure breakdown by reason.
Compliance that doesn’t cost you sales
Zana’s opt-outs are topic-scoped: a customer can opt out of marketing and still receive their invoices and receipts - you don’t lose a paying customer because they muted your promos. An inbound WhatsApp STOP or UNSUBSCRIBE creates the opt-out automatically. Opted-out numbers are dropped at build time, never queued, and your customers never see the carrier behind the send.
What you’ll need
CRM campaigns are on Pro (KES 2,500/month) and up. Messaging is prepaid pay-as-you-go - SMS from KES 1.00/segment, WhatsApp from KES 1.50 per utility message - so you only pay for what you send. Connect your SMS or WhatsApp sender, import your contacts, and send a test before your first real campaign.