diff --git a/src/yunohost/app.py b/src/yunohost/app.py
index 0f4c14b7a..5b6d1a7f8 100644
--- a/src/yunohost/app.py
+++ b/src/yunohost/app.py
@@ -69,6 +69,10 @@ re_app_instance_name = re.compile(
     r"^(?P<appid>[\w-]+?)(__(?P<appinstancenb>[1-9][0-9]*))?$"
 )
 
+APP_REPO_URL = re.compile(
+    r"^https://[a-zA-Z0-9-_.]+/[a-zA-Z0-9-_./]+/[a-zA-Z0-9-_.]+_ynh(/?(-/)?tree/[a-zA-Z0-9-_]+)?(\.git)?/?$"
+)
+
 APP_FILES_TO_COPY = [
     "manifest.json",
     "manifest.toml",
@@ -1971,13 +1975,24 @@ def _set_default_ask_questions(arguments):
     return arguments
 
 
+def _is_app_repo_url(string: str) -> bool:
+
+    string = string.strip()
+
+    # Dummy test for ssh-based stuff ... should probably be improved somehow
+    if '@' in string:
+        return True
+
+    return APP_REPO_URL.match(string)
+
+
 def _app_quality(app: str) -> str:
     """
        app may in fact be an app name, an url, or a path
     """
 
     raw_app_catalog = _load_apps_catalog()["apps"]
-    if app in raw_app_catalog or ("@" in app) or ("http://" in app) or ("https://" in app):
+    if app in raw_app_catalog or _is_app_repo_url(app):
 
         # If we got an app name directly (e.g. just "wordpress"), we gonna test this name
         if app in raw_app_catalog:
@@ -2027,10 +2042,14 @@ def _extract_app(src: str) -> Tuple[Dict, str]:
         revision = str(app_info["git"]["revision"])
         return _extract_app_from_gitrepo(url, branch, revision, app_info)
     # App is a git repo url
-    elif ("@" in src) or ("http://" in src) or ("https://" in src):
+    elif _is_app_repo_url(src):
         url = src
         branch = "master"
         revision = "HEAD"
+        # gitlab urls may look like 'https://domain/org/group/repo/-/tree/testing'
+        # compated to github urls looking like 'https://domain/org/repo/tree/testing'
+        if '/-/' in url:
+            url = url.replace('/-/', '/')
         if "/tree/" in url:
             url, branch = url.split("/tree/", 1)
         return _extract_app_from_gitrepo(url, branch, revision, {})
@@ -2038,6 +2057,8 @@ def _extract_app(src: str) -> Tuple[Dict, str]:
     elif os.path.exists(src):
         return _extract_app_from_folder(src)
     else:
+        if "http://" in src or "https://" in src:
+            logger.error(f"{src} is not a valid app url: app url are expected to look like https://domain.tld/path/to/repo_ynh")
         raise YunohostValidationError("app_unknown")
 
 
diff --git a/src/yunohost/tests/test_appurl.py b/src/yunohost/tests/test_appurl.py
index 5954d239a..d50877445 100644
--- a/src/yunohost/tests/test_appurl.py
+++ b/src/yunohost/tests/test_appurl.py
@@ -4,7 +4,7 @@ import os
 from .conftest import get_test_apps_dir
 
 from yunohost.utils.error import YunohostError
-from yunohost.app import app_install, app_remove
+from yunohost.app import app_install, app_remove, _is_app_repo_url
 from yunohost.domain import _get_maindomain, domain_url_available
 from yunohost.permission import _validate_and_sanitize_permission_url
 
@@ -28,6 +28,34 @@ def teardown_function(function):
         pass
 
 
+def test_repo_url_definition():
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foobar123_ynh")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foobar123_ynh/")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foobar123_ynh.git")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foobar123_ynh/tree/testing")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foobar123_ynh/tree/testing/")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foo-bar-123_ynh")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/foo_bar_123_ynh")
+    assert _is_app_repo_url("https://github.com/YunoHost-Apps/FooBar123_ynh")
+    assert _is_app_repo_url("https://github.com/labriqueinternet/vpnclient_ynh")
+    assert _is_app_repo_url("https://framagit.org/YunoHost/apps/nodebb_ynh")
+    assert _is_app_repo_url("https://framagit.org/YunoHost/apps/nodebb_ynh/-/tree/testing")
+    assert _is_app_repo_url("https://gitlab.com/yunohost-apps/foobar_ynh")
+    assert _is_app_repo_url("https://code.antopie.org/miraty/qr_ynh")
+    assert _is_app_repo_url("https://gitlab.domainepublic.net/Neutrinet/neutrinet_ynh/-/tree/unstable")
+    assert _is_app_repo_url("git@github.com:YunoHost-Apps/foobar_ynh.git")
+
+    assert not _is_app_repo_url("github.com/YunoHost-Apps/foobar_ynh")
+    assert not _is_app_repo_url("http://github.com/YunoHost-Apps/foobar_ynh")
+    assert not _is_app_repo_url("https://github.com/YunoHost-Apps/foobar_wat")
+    assert not _is_app_repo_url("https://github.com/YunoHost-Apps/foobar_ynh_wat")
+    assert not _is_app_repo_url("https://github.com/YunoHost-Apps/foobar/tree/testing")
+    assert not _is_app_repo_url("https://github.com/YunoHost-Apps/foobar_ynh_wat/tree/testing")
+    assert not _is_app_repo_url("https://framagit.org/YunoHost/apps/")
+    assert not _is_app_repo_url("https://framagit.org/YunoHost/apps/pwet")
+    assert not _is_app_repo_url("https://framagit.org/YunoHost/apps/pwet_foo")
+
+
 def test_urlavailable():
 
     # Except the maindomain/macnuggets to be available