Guides
Direct answers to common questions about verifying messages, calls and web experiences from real phones on real SIMs.
- Monitor OTP/SMS
How do you verify that OTP codes are actually delivered to real phones?
Send the OTP from your own system to a real phone number on a real SIM that an independent observer controls, then record whether the message arrived inside a declared time window, which sender it showed, how many milliseconds it took and whether the content arrived intact. A message that does not arrive inside the window is recorded as silence: a measurement, not an error. Witnio's Monitor OTP/SMS does this on physical Android phones and signs every result with Ed25519.
Read the guide → - Voice / Call Assurance
How do you verify that outbound calls actually ring, and what caller ID the recipient sees?
Call a real number on a real SIM that an independent observer controls, and record on the receiving phone whether the call arrived, how long it took to ring, which caller ID was displayed, any name or Spam/Scam label shown, and the call log entry with its state and duration, backed by a screenshot. Your dialer's own logs cannot show what the recipient's screen displayed. Witnio's Voice / Call Assurance records these fields on physical Android phones and signs each result with Ed25519.
Read the guide → - Access Monitor
What is the difference between synthetic monitoring and real-device monitoring?
Synthetic monitoring runs scripted checks from servers in datacenters, usually with a headless browser. It is cheap and frequent, and it tells you whether your site answers a datacenter. Real-device monitoring loads the same page on a physical phone on a carrier network, so it also catches what only real mobile users meet: blocks by user agent or location, bot challenges, 403 pages and mobile-only redirects. Witnio's Access Monitor runs these checks on real Android phones and records DNS, TLS, HTTP result, redirects, challenge detection, load time and a signed screenshot.
Read the guide → - Consent & Cookie Check
What evidence does a cookie-consent audit need?
A cookie-consent audit needs reproducible records of what a real visitor's browser received: whether the banner appeared, which choices it offered on the first screen, which cookies and third-party trackers were set before any choice, what changed after accepting or rejecting, screenshots of each state, and timestamps with integrity protection. Witnio's Consent & Cookie Check produces those records from a real Android phone on a real SIM. It observes as a visitor outside the EU, not as a visitor located in the EU, and it is supporting evidence, not a legal opinion.
Read the guide → - Geo / SIM Verification
What is SIM-based geo verification, and how is it different from IP or GPS checks?
SIM-based geo verification checks what a user in a given market sees by loading your site or app on a real phone with a local SIM, connected through that carrier's mobile network. The page receives the same signals a local user sends: a carrier IP address, the SIM's country and carrier codes, and a mobile device. IP-based checks rely on a VPN or datacenter address that many sites detect, and GPS is a location the device reports, which most websites never read. Witnio's Geo / SIM Verification records content, price, currency, language and availability from that real context.
Read the guide → - Compliance Evidence Pro
What is the difference between compliance evidence and a compliance certification?
A certification is a formal statement by an independent, accredited assessor that an organization meets a standard over a defined scope and period. Evidence is the records that let you, and later that assessor, check whether a control actually worked: what happened, when, and proof that the record was not altered. Evidence supports a certification; it never replaces one. Witnio's Compliance Evidence Pro produces signed, verifiable evidence packages for your own audits and controls. It does not certify anything and does not make any customer compliant.
Read the guide → - Spam Label Monitor · Coming soon
How can you tell if your business number is being labeled as spam?
The only reliable way is to look at the recipient's screen. Place a test call or send a test message from your real number to a real phone, and record exactly what the phone shows: the caller ID, any label such as "Spam" or "Suspected scam", and which device, OS, dialer and dialer version displayed it. Labels depend on that exact combination, so one screenshot does not generalize. Witnio's Spam Label Monitor is designed to record those fields with signed evidence. It is coming soon and not sold yet.
Read the guide → - A2P / 10DLC Delivery Verification · Coming soon
What should an A2P 10DLC delivery verification checklist include?
An A2P 10DLC checklist has two halves. Before sending: a registered brand, an approved campaign whose use case matches your messages, numbers attached to that campaign, clear opt-in, working STOP and HELP replies, and links on your own domain. After sending: independent proof that messages reached a real US handset, with the sender shown, the latency, intact content and intact links. Provider receipts cover the first hop only. Witnio's A2P / 10DLC Delivery Verification is coming soon; it needs a real US SIM, which is not installed yet.
Read the guide → - Web Assurance · Coming soon
What does real-device web assurance cover, and when do you need it?
Real-device web assurance checks a website or mobile web app from the phone a customer actually uses, on three questions at once: does it load (availability, DNS, TLS, redirects, bot challenges), does it respect consent (banner, choices, cookies before and after), and does it work on modest hardware (load timing, memory, visible failures). You need it when mobile customers are a large share of revenue and datacenter checks disagree with what support hears. Witnio's Web Assurance bundle combines Access Monitor, Consent & Cookie Check and Low-end Device Check. It is coming soon.
Read the guide → - Low-end Device Check · Coming soon
How do you test whether an app or website works on low-end Android phones?
Run it on a physical low-end phone and measure what the user feels: page load timing, app cold-start time, memory use, janky frames, and visible failures such as crashes and "app not responding" events, together with the device's real profile (RAM, CPU cores, free storage, OS). Emulators on a desktop do not reproduce the memory and CPU pressure of cheap hardware faithfully. Witnio's Low-end Device Check records these measurements with signed screenshots. It is coming soon, and until a real low-end phone joins the fleet each run honestly reports the mid-range tier it ran on.
Read the guide →