diff --git a/pyproject.toml b/pyproject.toml
index a917c55..4f4ca99 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "phase_dev"
-version = "2.1.0"
+version = "2.1.1"
 description = "Python SDK for Phase secrets manager"
 readme = "README.md"
 requires-python = ">=3.10"
diff --git a/requirements.txt b/requirements.txt
index 5afcd6a..daae70d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 certifi==2023.7.22
-cffi==1.15.1
+cffi==1.17.1
 charset-normalizer==3.1.0
 exceptiongroup==1.1.1
 idna==3.4
@@ -9,6 +9,6 @@ pluggy==1.0.0
 pycparser==2.21
 PyNaCl==1.5.0
 pytest==7.3.1
-requests==2.31.0
+requests==2.32.0
 tomli==2.0.1
 urllib3==2.2.2
diff --git a/src/phase/utils/const.py b/src/phase/utils/const.py
index 95410f1..9d3c971 100644
--- a/src/phase/utils/const.py
+++ b/src/phase/utils/const.py
@@ -1,7 +1,7 @@
 import os
 import re
 
-__version__ = "2.1.0"
+__version__ = "2.1.1"
 __ph_version__ = "v1"
 
 
diff --git a/src/phase/utils/secret_referencing.py b/src/phase/utils/secret_referencing.py
index cb7fb12..2242be2 100644
--- a/src/phase/utils/secret_referencing.py
+++ b/src/phase/utils/secret_referencing.py
@@ -1,14 +1,14 @@
-import re
 from typing import Dict, List
 from .exceptions import EnvironmentNotFoundException
 from .const import SECRET_REF_REGEX
+from .phase_io import Phase
 
 """
     Secret Referencing Syntax:
 
     This documentation explains the syntax used for referencing secrets within the configuration. 
-    Secrets can be referenced both locally (within the same environment) and across different environments, 
-    with or without specifying a path.
+    Secrets can be referenced locally (within the same environment), across different environments, 
+    and across different applications, with or without specifying a path.
 
     Syntax Patterns:
 
@@ -40,8 +40,16 @@
         - Secret Key: `STRIPE_KEY`
         - Description: References a secret named `STRIPE_KEY` located at `/backend/payments/` in the current environment.
 
+    5. Cross-Application Reference:
+        Syntax: `${backend_api::production./frontend/SECRET_KEY}`
+        - Application: Different application (e.g., `backend_api`).
+        - Environment: Different environment (e.g., `production`).
+        - Path: Specifies a path within the environment (`/frontend/`).
+        - Secret Key: `SECRET_KEY`
+        - Description: References a secret named `SECRET_KEY` located at `/frontend/` in the `production` environment of the `backend_api` application.
+
     Note:
-    The syntax allows for flexible secret management, enabling both straightforward local references and more complex cross-environment references.
+    The syntax allows for flexible secret management, enabling local references, cross-environment references, and cross-application references.
 """
 
 
@@ -74,12 +82,13 @@ def resolve_secret_reference(ref: str, secrets_dict: Dict[str, Dict[str, Dict[st
     """
     Resolves a single secret reference to its actual value by fetching it from the specified environment.
     
-    The function supports both local and cross-environment secret references, allowing for flexible secret management.
+    The function supports local, cross-environment, and cross-application secret references, allowing for flexible secret management.
     Local references are identified by the absence of a dot '.' in the reference string, implying the current environment.
     Cross-environment references include an environment name, separated by a dot from the rest of the path.
+    Cross-application references use '::' to separate the application name from the rest of the reference.
     
     Args:
-        ref (str): The secret reference string, which could be a local or cross-environment reference.
+        ref (str): The secret reference string, which could be a local, cross-environment, or cross-application reference.
         secrets_dict (Dict[str, Dict[str, Dict[str, str]]]): A dictionary containing known secrets.
         phase ('Phase'): An instance of the Phase class to fetch secrets.
         current_application_name (str): The name of the current application.
@@ -88,10 +97,17 @@ def resolve_secret_reference(ref: str, secrets_dict: Dict[str, Dict[str, Dict[st
     Returns:
         str: The resolved secret value or the original reference if not resolved.
     """
+    original_ref = ref  # Store the original reference
+    app_name = current_application_name 
     env_name = current_env_name
     path = "/"  # Default root path
     key_name = ref
 
+    # Check if this is a cross-application reference
+    if "::" in ref:
+        parts = ref.split("::", 1)
+        app_name, ref = parts[0], parts[1]
+        
     # Parse the reference to identify environment, path, and secret key.
     if "." in ref:  # Cross-environment references
         parts = ref.split(".", 1)
@@ -112,15 +128,15 @@ def resolve_secret_reference(ref: str, secrets_dict: Dict[str, Dict[str, Dict[st
                 return secrets_dict[env_name]['/'][key_name]
 
         # If the secret is not found in secrets_dict, try to fetch it from Phase
-        fetched_secrets = phase.get(env_name=env_name, app_name=current_application_name, keys=[key_name], path=path)
+        fetched_secrets = phase.get(env_name=env_name, app_name=app_name, keys=[key_name], path=path)
         for secret in fetched_secrets:
             if secret["key"] == key_name:
                 return secret["value"]
     except EnvironmentNotFoundException:
         pass
 
-    # Return the reference as is if not resolved
-    return f"${{{ref}}}"
+    # Return the original secret value as is if not resolved
+    return f"${{{original_ref}}}"
 
 
 def resolve_all_secrets(value: str, all_secrets: List[Dict[str, str]], phase: 'Phase', current_application_name: str, current_env_name: str) -> str:
diff --git a/tests/test_secret_referencing.py b/tests/test_secret_referencing.py
index efd6a95..9de28e0 100644
--- a/tests/test_secret_referencing.py
+++ b/tests/test_secret_referencing.py
@@ -29,8 +29,12 @@
 # Mock Phase class
 class MockPhase:
     def get(self, env_name, app_name, keys, path):
-        if env_name == "prod" and path == "/frontend":
+        if env_name == "prod" and path == "/frontend" and app_name == "test_app":
             return [{"key": "SECRET_KEY", "value": "prod_secret_value"}]
+        if env_name == "production" and path == "/" and app_name == "backend_api":
+            return [{"key": "API_KEY", "value": "backend_api_key"}]
+        if env_name == "staging" and path == "/auth" and app_name == "auth_service":
+            return [{"key": "AUTH_TOKEN", "value": "auth_service_token"}]
         raise EnvironmentNotFoundException(env_name=env_name)
 
 @pytest.fixture
@@ -115,4 +119,41 @@ def test_resolve_local_reference_missing_path(phase, current_application_name, c
 def test_resolve_invalid_reference_format(phase, current_application_name, current_env_name):
     ref = "invalid_format"
     resolved_value = resolve_secret_reference(ref, secrets_dict, phase, current_application_name, current_env_name)
-    assert resolved_value == "${invalid_format}"
\ No newline at end of file
+    assert resolved_value == "${invalid_format}"
+
+# Tests for Cross-Application References
+def test_resolve_cross_app_reference(phase, current_application_name, current_env_name):
+    ref = "backend_api::production.API_KEY"
+    resolved_value = resolve_secret_reference(ref, secrets_dict, phase, current_application_name, current_env_name)
+    assert resolved_value == "backend_api_key"
+
+def test_resolve_cross_app_reference_with_path(phase, current_application_name, current_env_name):
+    ref = "auth_service::staging./auth/AUTH_TOKEN"
+    resolved_value = resolve_secret_reference(ref, secrets_dict, phase, current_application_name, current_env_name)
+    assert resolved_value == "auth_service_token"
+
+def test_resolve_missing_cross_app_key(phase, current_application_name, current_env_name):
+    ref = "another_app::dev.MISSING_KEY"
+    resolved_value = resolve_secret_reference(ref, secrets_dict, phase, current_application_name, current_env_name)
+    assert resolved_value == "${another_app::dev.MISSING_KEY}"
+
+def test_resolve_all_secrets_with_cross_app(phase, current_application_name, current_env_name):
+    value = "Use this key: ${KEY}, this cross-app key: ${backend_api::production.API_KEY}, and this path key: ${/backend/payments/STRIPE_KEY}"
+    all_secrets = [
+        {"environment": "current", "path": "/", "key": "KEY", "value": "value1"},
+        {"environment": "current", "path": "/backend/payments", "key": "STRIPE_KEY", "value": "stripe_value"}
+    ]
+    resolved_value = resolve_all_secrets(value, all_secrets, phase, current_application_name, current_env_name)
+    expected_value = "Use this key: value1, this cross-app key: backend_api_key, and this path key: stripe_value"
+    assert resolved_value == expected_value
+
+# Complex Case: Mixed references including cross-app with missing values
+def test_resolve_mixed_references_with_cross_app(phase, current_application_name, current_env_name):
+    value = "Local: ${KEY}, Cross-Env: ${staging.DEBUG}, Cross-App: ${backend_api::production.API_KEY}, Missing Cross-App: ${missing_app::prod.KEY}"
+    all_secrets = [
+        {"environment": "current", "path": "/", "key": "KEY", "value": "value1"},
+        {"environment": "staging", "path": "/", "key": "DEBUG", "value": "staging_debug_value"}
+    ]
+    resolved_value = resolve_all_secrets(value, all_secrets, phase, current_application_name, current_env_name)
+    expected_value = "Local: value1, Cross-Env: staging_debug_value, Cross-App: backend_api_key, Missing Cross-App: ${missing_app::prod.KEY}"
+    assert resolved_value == expected_value
\ No newline at end of file