diff --git a/src/interface.c b/src/interface.c
index b69dc8a8..c3bb4a5d 100644
--- a/src/interface.c
+++ b/src/interface.c
@@ -407,7 +407,7 @@ void c_interface_select_diskette( int drive )
         if (entries <= 0)
         {
             DISKERR_SHOWERR("Problem reading directory");
-            snprintf(disk_path, PATH_MAX, "%s", getenv("HOME"));
+            snprintf(disk_path, PATH_MAX, "%s", HOMEDIR);
             nextdir = true;
             continue;
         }
@@ -1545,7 +1545,7 @@ static void *interface_thread(void *current_key)
     char *path = NULL;
     prefs_copyStringValue(PREF_DOMAIN_INTERFACE, PREF_DISK_PATH, &path);
     if (!path) {
-        ASPRINTF(&path, "%s", getenv("HOME"));
+        ASPRINTF(&path, "%s", HOMEDIR);
     }
     strncpy(disk_path, path, PATH_MAX-1);
     disk_path[PATH_MAX-1] = '\0';
diff --git a/src/meta/debug.c b/src/meta/debug.c
index 9fc42d17..b2756d73 100644
--- a/src/meta/debug.c
+++ b/src/meta/debug.c
@@ -2366,7 +2366,7 @@ YY_RULE_SETUP
 {
 #if CPU_TRACING
     char *buf = NULL;
-    asprintf(&buf, "%s/%s", getenv("HOME"), "cputrace.txt");
+    asprintf(&buf, "%s/%s", HOMEDIR, "cputrace.txt");
     cpu65_trace_toggle(buf);
     FREE(buf);
 #else
@@ -2381,7 +2381,7 @@ YY_RULE_SETUP
 {
 #if DISK_TRACING
     char *buf = NULL;
-    asprintf(&buf, "%s/%s", getenv("HOME"), "disktrace.txt");
+    asprintf(&buf, "%s/%s", HOMEDIR, "disktrace.txt");
     c_toggle_disk_trace_6(buf, NULL);
     FREE(buf);
 #else
diff --git a/src/meta/debug.l b/src/meta/debug.l
index 2c572751..43b29eaa 100644
--- a/src/meta/debug.l
+++ b/src/meta/debug.l
@@ -852,7 +852,7 @@ ADDRS	[0-9a-fA-F]+
 {BOS}cput?r?a?c?e?{EOS} {
 #if CPU_TRACING
     char *buf = NULL;
-    asprintf(&buf, "%s/%s", getenv("HOME"), "cputrace.txt");
+    asprintf(&buf, "%s/%s", HOMEDIR, "cputrace.txt");
     cpu65_trace_toggle(buf);
     FREE(buf);
 #else
@@ -863,7 +863,7 @@ ADDRS	[0-9a-fA-F]+
 {BOS}diskt?r?a?c?e?{EOS} {
 #if DISK_TRACING
     char *buf = NULL;
-    asprintf(&buf, "%s/%s", getenv("HOME"), "disktrace.txt");
+    asprintf(&buf, "%s/%s", HOMEDIR, "disktrace.txt");
     c_toggle_disk_trace_6(buf, NULL);
     FREE(buf);
 #else
diff --git a/src/misc.h b/src/misc.h
index a2b9dc37..bf743420 100644
--- a/src/misc.h
+++ b/src/misc.h
@@ -25,6 +25,12 @@ enum {
 // top installation directory
 extern const char *data_dir;
 
+#if MOBILE_DEVICE
+#   define HOMEDIR data_dir
+#else
+#   define HOMEDIR getenv("HOME")
+#endif
+
 // global ref to CLI args
 extern char **argv;
 extern int argc;
diff --git a/src/prefs.c b/src/prefs.c
index 2814026b..e587b8c8 100644
--- a/src/prefs.c
+++ b/src/prefs.c
@@ -47,7 +47,7 @@ void prefs_load(void) {
     }
 
     if (!prefsFile) {
-        ASPRINTF(&prefsFile, "%s/.apple2.json", getenv("HOME"));
+        ASPRINTF(&prefsFile, "%s/.apple2.json", HOMEDIR);
     }
     assert(prefsFile);
 
diff --git a/src/test/testcommon.c b/src/test/testcommon.c
index 7b48d635..e5d40c6e 100644
--- a/src/test/testcommon.c
+++ b/src/test/testcommon.c
@@ -45,7 +45,7 @@ void test_common_init(void) {
     emulator_ctors();
 
     char *envvar = NULL;
-    ASPRINTF(&envvar, "APPLE2IX_JSON=%s/.apple2.test.json", getenv("HOME"));
+    ASPRINTF(&envvar, "APPLE2IX_JSON=%s/.apple2.test.json", HOMEDIR);
     assert(envvar);
     putenv(envvar);
     LEAK(envvar);
diff --git a/src/test/testcommon.h b/src/test/testcommon.h
index ae106255..75daa394 100644
--- a/src/test/testcommon.h
+++ b/src/test/testcommon.h
@@ -23,12 +23,6 @@
 #   include "test/sha1.h"
 #endif
 
-#ifdef ANDROID
-#   define HOMEDIR data_dir
-#else
-#   define HOMEDIR getenv("HOME")
-#endif
-
 #define TEST_FINISHED 0xff
 #define MIXSWITCH_ADDR 0x1f32   // PEEK(7986) -- NOTE : value is hardcoded in various places
 #define WATCHPOINT_ADDR 0x1f33  // PEEK(7987) -- NOTE : value is hardcoded in various places
diff --git a/src/test/testprefs.c b/src/test/testprefs.c
index ff1891e0..cbe33bd2 100644
--- a/src/test/testprefs.c
+++ b/src/test/testprefs.c
@@ -272,7 +272,7 @@ TEST test_json_serialization() {
     ASSERT(tokCount > 0);
 
     char *tmpFile = NULL;
-    ASPRINTF(&tmpFile, "%s/json-XXXXXX", getenv("HOME"));
+    ASPRINTF(&tmpFile, "%s/json-XXXXXX", HOMEDIR);
     ASSERT(tmpFile);
     int fd = mkstemp(tmpFile);
     ASSERT(fd > 0);
@@ -304,7 +304,7 @@ TEST test_json_serialization_pretty() {
     ASSERT(parsedData);
 
     char *tmpFile = NULL;
-    ASPRINTF(&tmpFile, "%s/json-pretty-XXXXXX", getenv("HOME"));
+    ASPRINTF(&tmpFile, "%s/json-pretty-XXXXXX", HOMEDIR);
     ASSERT(tmpFile);
     int fd = mkstemp(tmpFile);
     ASSERT(fd > 0);
@@ -1896,12 +1896,12 @@ TEST test_prefs_set_props() {
 TEST test_prefs_load_and_save() {
 
     char *apple2JSON = NULL;
-    ASPRINTF(&apple2JSON, "%s/%s", getenv("HOME"), TEST_JSON);
+    ASPRINTF(&apple2JSON, "%s/%s", HOMEDIR, TEST_JSON);
     ASSERT(apple2JSON);
     unlink(apple2JSON);
 
     char *apple2JSONEnv = NULL;
-    ASPRINTF(&apple2JSONEnv, "APPLE2IX_JSON=%s/%s", getenv("HOME"), TEST_JSON);
+    ASPRINTF(&apple2JSONEnv, "APPLE2IX_JSON=%s/%s", HOMEDIR, TEST_JSON);
     ASSERT(apple2JSONEnv);
     putenv(apple2JSONEnv);
     LEAK(apple2JSONEnv);