diff --git a/.github/workflows/validate_json.yml b/.github/workflows/validate_apps.yml
similarity index 85%
rename from .github/workflows/validate_json.yml
rename to .github/workflows/validate_apps.yml
index 0502b6e..b58bb0b 100644
--- a/.github/workflows/validate_json.yml
+++ b/.github/workflows/validate_apps.yml
@@ -16,6 +16,6 @@ jobs:
       - uses: actions/setup-node@v1
         with:
           node-version: 14
-      - run: npm ci && npm run validate_json && npm run formatter
+      - run: npm ci && npm run validate_apps && npm run formatter
         env:
           GITHUB_PERSONAL_TOKEN: ${{secrets.GITHUB_PERSONAL_TOKEN}}
diff --git a/package.json b/package.json
index cb7fe85..bc45323 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,7 @@
     "formatter": "prettier --check './public/**/*.(json|yml)'",
     "formatter-write": "prettier --write './public/**/*.(json|yml)'",
     "build": "rm -rf ./dist/ && mkdir -p dist && node ./scripts/build_one_click_apps.js && node ./scripts/build_one_click_apps_from_v4.js",
-    "validate_json": "node ./scripts/validate_json.js",
+    "validate_apps": "node ./scripts/validate_apps.js",
     "publish": "npm run build && ./scripts/publish-from-actions.sh"
   },
   "repository": {
diff --git a/scripts/validate_apps.js b/scripts/validate_apps.js
new file mode 100644
index 0000000..5923fac
--- /dev/null
+++ b/scripts/validate_apps.js
@@ -0,0 +1,138 @@
+ /*jshint esversion: 6 */
+ const path = require('path');
+ const yaml = require('yaml');
+ const fs = require('fs-extra');
+
+ const PUBLIC = `public`;
+ const pathOfPublic = path.join(__dirname, '..', PUBLIC);
+
+
+ // validating version 4
+ function validateV4() {
+
+     const version = '4';
+     const pathOfVersion = path.join(pathOfPublic, 'v' + version);
+     const pathOfApps = path.join(pathOfVersion, 'apps');
+
+     return fs.readdir(pathOfApps)
+         .then(function (items) {
+
+             const apps = items.filter(v => v.includes('.yml'));
+
+             if (items.length !== apps.length) {
+                 throw new Error('All files in v4 must end with .yml');
+             }
+
+             for (var i = 0; i < apps.length; i++) {
+                 const contentString = fs.readFileSync(path.join(pathOfApps, apps[i]), 'utf-8');
+                 const content = yaml.parse(contentString);
+                 const captainVersion = (content.captainVersion + '');
+                 const versionString = (version + '');
+                 if (versionString !== captainVersion)
+                     throw new Error(`unmatched versions   ${versionString}  ${captainVersion} for ${apps[i]}`);
+
+                 apps[i] = apps[i].replace('.yml', '');
+
+                 if (!content.caproverOneClickApp) {
+                     throw new Error(`Cannot find caproverOneClickApp for ${apps[i]}`);
+                 }
+
+                 if (!content.caproverOneClickApp.description) {
+                     throw new Error(`Cannot find description for ${apps[i]}`);
+                 }
+
+                 if (!content.caproverOneClickApp.instructions ||
+                     !content.caproverOneClickApp.instructions.start ||
+                     !content.caproverOneClickApp.instructions.end) {
+                     throw new Error(`Cannot find instructions.start or instructions.end for ${apps[i]}`);
+                 }
+
+                 if (!content.services) {
+                     throw new Error(`Cannot find services for ${apps[i]}`);
+                 }
+
+                 Object.keys(content.services).forEach(
+                     (serviceName) => { // jshint ignore:line
+                         const s = content.services[serviceName];
+                         if (s.image && s.image.endsWith(':latest')) {
+                             throw new Error(`"latest" tag is not allowed as it can change and break the setup, see ${apps[i]}`);
+                         }
+                     });
+
+                 const logoFileName = apps[i] + '.png';
+
+                 const logoFullPath = path.join(pathOfVersion, 'logos', logoFileName);
+
+                 if (!fs.existsSync(logoFullPath) ||
+                     !fs.statSync(logoFullPath).isFile()) {
+                     let printablePath = logoFullPath;
+                     printablePath = printablePath.substr(printablePath.indexOf(`/${PUBLIC}`));
+                     throw new Error(`Cannot find logo for ${apps[i]} ${printablePath}`);
+                 }
+
+                 console.log(`Validated ${apps[i]}`);
+
+             }
+
+         });
+ }
+
+ // validating version 2
+ function validateV2() {
+
+     const version = '2';
+     const pathOfVersion = path.join(pathOfPublic, 'v' + version);
+     const pathOfApps = path.join(pathOfVersion, 'apps');
+
+     return fs.readdir(pathOfApps)
+         .then(function (items) {
+
+             const apps = items.filter(v => v.includes('.json'));
+
+             if (items.length !== apps.length) {
+                 throw new Error('All files in v2 must end with .json');
+             }
+
+             for (var i = 0; i < apps.length; i++) {
+                 const contentString = fs.readFileSync(path.join(pathOfApps, apps[i]));
+                 const content = JSON.parse(contentString);
+                 const captainVersion = (content.captainVersion + '');
+                 const versionString = (version + '');
+                 if (versionString !== captainVersion)
+                     throw new Error(`unmatched versions   ${versionString}  ${captainVersion} for ${apps[i]}`);
+
+                 apps[i] = apps[i].replace('.json', '');
+
+                 if (!content.description) {
+                     throw new Error(`Cannot find description for ${apps[i]}`);
+                 }
+
+                 const logoFileName = apps[i] + '.png';
+
+                 const logoFullPath = path.join(pathOfVersion, 'logos', logoFileName);
+
+                 if (!fs.existsSync(logoFullPath) ||
+                     !fs.statSync(logoFullPath).isFile()) {
+                     let printablePath = logoFullPath;
+                     printablePath = printablePath.substr(printablePath.indexOf(`/${PUBLIC}`));
+                     throw new Error(`Cannot find logo for ${apps[i]} ${printablePath}`);
+                 }
+
+                 console.log(`Validated ${apps[i]}`);
+
+             }
+
+         });
+ }
+
+ Promise.resolve()
+     .then(function () {
+         return validateV2();
+     })
+     .then(function () {
+         return validateV4();
+     })
+     .catch(function (err) {
+         console.error(err);
+         process.exit(127);
+     });
\ No newline at end of file
diff --git a/scripts/validate_json.js b/scripts/validate_json.js
deleted file mode 100644
index 3e58338..0000000
--- a/scripts/validate_json.js
+++ /dev/null
@@ -1,104 +0,0 @@
- /*jshint esversion: 6 */
- const path = require('path');
- const fs = require('fs-extra');
-
- const PUBLIC = `public`;
- const pathOfPublic = path.join(__dirname, '..', PUBLIC);
-
-
- // validating version 4
- //  function validateV4() {
-
- //      const version = '2';
- //      const pathOfVersion = path.join(pathOfPublic, 'v' + version);
- //      const pathOfApps = path.join(pathOfVersion, 'apps');
-
- //      return fs.readdir(pathOfApps)
- //          .then(function (items) {
-
- //              const apps = items.filter(v => v.includes('.json'));
-
- //              for (var i = 0; i < apps.length; i++) {
- //                  const contentString = fs.readFileSync(path.join(pathOfApps, apps[i]));
- //                  const content = JSON.parse(contentString);
- //                  const captainVersion = (content.captainVersion + '');
- //                  const versionString = (version + '');
- //                  if (versionString !== captainVersion)
- //                      throw new Error(`unmatched versions   ${versionString}  ${captainVersion} for ${apps[i]}`);
-
- //                  apps[i] = apps[i].replace('.json', '');
-
- //                  if (!content.description){
- //                     throw new Error(`Cannot find description for ${apps[i]}`);
- //                  }
-
- //                  const logoFileName = apps[i] + '.png';
-
- //                  const logoFullPath = path.join(pathOfVersion, 'logos', logoFileName);
-
- //                  if (!fs.existsSync(logoFullPath) ||
- //                      !fs.statSync(logoFullPath).isFile()) {
- //                      let printablePath = logoFullPath;
- //                      printablePath = printablePath.substr(printablePath.indexOf(`/${PUBLIC}`));
- //                      throw new Error(`Cannot find logo for ${apps[i]} ${printablePath}`);
- //                  }
-
- //                  console.log(`Validated ${apps[i]}`);
-
- //              }
-
- //          });
- //  }
-
- // validating version 2
- function validateV2() {
-
-     const version = '2';
-     const pathOfVersion = path.join(pathOfPublic, 'v' + version);
-     const pathOfApps = path.join(pathOfVersion, 'apps');
-
-     return fs.readdir(pathOfApps)
-         .then(function (items) {
-
-             const apps = items.filter(v => v.includes('.json'));
-
-             for (var i = 0; i < apps.length; i++) {
-                 const contentString = fs.readFileSync(path.join(pathOfApps, apps[i]));
-                 const content = JSON.parse(contentString);
-                 const captainVersion = (content.captainVersion + '');
-                 const versionString = (version + '');
-                 if (versionString !== captainVersion)
-                     throw new Error(`unmatched versions   ${versionString}  ${captainVersion} for ${apps[i]}`);
-
-                 apps[i] = apps[i].replace('.json', '');
-
-                 if (!content.description) {
-                     throw new Error(`Cannot find description for ${apps[i]}`);
-                 }
-
-                 const logoFileName = apps[i] + '.png';
-
-                 const logoFullPath = path.join(pathOfVersion, 'logos', logoFileName);
-
-                 if (!fs.existsSync(logoFullPath) ||
-                     !fs.statSync(logoFullPath).isFile()) {
-                     let printablePath = logoFullPath;
-                     printablePath = printablePath.substr(printablePath.indexOf(`/${PUBLIC}`));
-                     throw new Error(`Cannot find logo for ${apps[i]} ${printablePath}`);
-                 }
-
-                 console.log(`Validated ${apps[i]}`);
-
-             }
-
-         });
- }
-
- Promise.resolve()
-     .then(function () {
-         return validateV2();
-     })
-     .catch(function (err) {
-         console.error(err);
-         process.exit(127);
-     });
\ No newline at end of file