Ad system
start.io
Most of the 157,457 apps that declare start.io reach it through a reseller: 98% have a RESELLER line, 34% a DIRECT one (23,947 files, 12,197 of them through Liftoff Monetize's account). 26% of the 127,053 lines checked name an account its sellers.json (2,519 sellers) does not list. 5 sellers left its sellers.json in the last 30 days.
- Apps declaring it
- 157,457
- Sellers in sellers.json
- 2,519
- Lines verified
- 55%
- Lines with errors
- 56,734
- Avg. supply path score
- 51.7 / 100
54,154 DIRECT · 154,439 RESELLER
0% confidential
73,499 of 134,738 checked lines
134,738 lines in total
165,387 apps scored
App counts, the sellers.json breakdown and the directory ranking are as of , recomputed daily (the same numbers as the directory). Line counts are recounted every 10 minutes. sellers.json last read 13 October 2026. The supply path score sums up how short and clean the declared paths are, 0 to 100 (how it is computed).
How to add start.io to app-ads.txt
One line per account, in the app-ads.txt at the root of the domain your App Store and Google Play listings name as the developer website.
start.io, YOUR_ACCOUNT_ID, DIRECT
start.io, YOUR_ACCOUNT_ID, RESELLER- Field 1:
start.io, the domain start.io uses in app-ads.txt. - Field 2: your account ID with start.io. It must equal the
seller_idin start.io's sellers.json. - Field 3: DIRECT if you hold the account, RESELLER if a partner holds it and sells your inventory. DIRECT vs RESELLER
- Field 4 (optional): a certification authority ID. Most lines naming start.io carry none, or different ones, so we do not suggest one.
sellers.json at a glance
- Status
- Published
- Sellers listed
- 2,519
- Confidential
- 0 (0%)
- Passthrough
- 0
- Removed, last 30 days
- 5
- Last read
- Oct 13, 2026
- PUBLISHER2,457
- INTERMEDIARY57
- BOTH5
Cross-check of lines naming start.io
- Verified 73,499
- Seller ID not found 35,273
- DIRECT but intermediary 7,736
- RESELLER but publisher 13,725
- Seller type BOTH 4,505
- Confidential seller 0
- No sellers.json 0
- Unchecked 0
Every line naming start.io is looked up in its sellers.json. What each status means
Common errors with start.io lines
-
Seller ID not found
35,273 lines
Ask start.io for the account ID it lists for you in its sellers.json, correct the line, or remove it if you no longer work with them. Buyers that check sellers.json drop these paths.
-
RESELLER but publisher
13,725 lines
If the account is yours, declare it DIRECT. If a partner holds it, ask start.io why the account is listed as PUBLISHER.
-
DIRECT but intermediary
7,736 lines
If a partner holds this account and resells your inventory, the line should say RESELLER. If the account is yours, ask start.io to list it as PUBLISHER.
-
Seller type BOTH
4,505 lines
The account is listed as BOTH, so sellers.json alone cannot tell a buyer which relationship applies. Nothing to fix on your side; buyers usually look at the seller's domain.
Intermediaries most declared as RESELLER
Accounts on start.io that its sellers.json lists as INTERMEDIARY or BOTH, by the number of app-ads.txt files declaring them. Confidential sellers are left out.
| Seller domain | Type | Files |
|---|---|---|
| vungle.com | INTERMEDIARY | 12,197 |
| unity.com | INTERMEDIARY | 9,084 |
| zmaticoo.com | INTERMEDIARY | 9,004 |
| opera.com | INTERMEDIARY | 8,973 |
| yandex.com | INTERMEDIARY | 5,774 |
| is.com | INTERMEDIARY | 4,319 |
| digitalturbine.com | BOTH | 4,090 |
| toponad.net | INTERMEDIARY | 2,603 |
Apps that declare start.io
| App | Store | Relationship | Status |
|---|---|---|---|
| Android | DIRECT + RESELLER | Live | |
| iOS | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live |
Questions about start.io
Does start.io publish a sellers.json?
Yes. Its file at https://www.start.io/sellers.json listed 2,519 sellers when we last read it on 13 October 2026: 2,457 publishers, 57 intermediaries and 5 listed as both; 0% are confidential.
How many apps declare start.io in app-ads.txt?
157,457 apps in Stoqlab's data (delisted apps included) declare start.io: 54,154 with at least one DIRECT line and 154,439 with at least one RESELLER line, across 23,947 app-ads.txt files, as of 13 October 2026 (recounted daily).
Why do start.io lines fail verification?
Of 134,738 lines naming start.io, 56,734 contradict its sellers.json. The most common case is "Seller ID not found", on 35,273 lines. Ask start.io for the account ID it lists for you in its sellers.json, correct the line, or remove it if you no longer work with them. Buyers that check sellers.json drop these paths.
Not sure whether your line should say DIRECT or RESELLER? DIRECT vs RESELLER in app-ads.txt
Sources: the public app-ads.txt files of tracked apps and the sellers.json of start.io. Something wrong? Tell us.