Callsling vs OneFill
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Callsling
This app allows users to send and receive calls and SMS messages over WiFi. It provides call tracking capabilities, linking incoming calls to their source like SEO or websites. The mobile application integrates with a cloud-based system for advanced lead generation and call handling.
- Send and receive calls via WiFi
- Send and receive SMS via WiFi
- Track calls from SEO and websites
- Configure new call tracking numbers
- Lead generation call tracking
- Advanced call handling
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Send and Receive Calls & SMS via WiFi. Track calls from SEO, Sites & more. Easy to use Mobile App which connects with the cloud-based application. You can configure a new call tracking number. Set up Lead Generation Call Tracking with advanced call handling.
OneFill
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OneFill is the fast way for licensed insurance agents to complete carrier applications. Enter your client's information once, then auto-fill any carrier's web application with a single tap — no retyping the same name, address, and date of birth on every portal. Built for agents who work across multiple carriers, OneFill keeps each client's details in one organized record and fills the fields for you, so you spend less time on data entry and more time with clients. KEY FEATURES One client record, every carrier — enter info once, reuse it everywhere One-tap fill — populate a carrier application instantly Two-way capture — keep your client record updated as you work Instant eligibility — see results and move on quickly Built-in safeguards — bank and card numbers are never auto-filled; you always enter those manually on the carrier site Works as a Safari extension on the carrier pages you already use OneFill is a productivity tool for licensed professionals. It does not sell insurance, provide quotes, or submit applications on your behalf.
Screenshots
Verdict
The clearest difference is update cadence: OneFill at every 8 days against Callsling's every 2 months. Callsling's advantage is iOS requirement (13.0 vs 17.6). On price, ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Callsling ships an update every 2 months, OneFill every 8 days. The most recent releases landed on October 2, 2026 and October 11, 2026 respectively.
| Parameter | Callsling | OneFill |
|---|---|---|
| Price | Free | Free |
| Rating | 3.9 (7 ratings) — better | — |
| Positive reviews | 66.7% of reviews | — |
| Number of ratings | 7 — better | — |
| Update frequency | Every 2 months | Every 8 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Ad-supported | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 13.0 — better | 17.6 |
| Further details — not scored | ||
| Size | 54 MB | 5 MB |
| Age rating | 4+ | 4+ |
| Developer | Dan Klein | Cassiel LLC |
In-app purchases
Callsling
No in-app purchases
OneFill
No in-app purchases
Questions
Is Callsling free?
Is OneFill free?
Do Callsling or OneFill have ads?
Which is updated more often, Callsling or OneFill?
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