diff --git a/lib/glucose-get-last.js b/lib/glucose-get-last.js
index <HASH>..<HASH> 100644
--- a/lib/glucose-get-last.js
+++ b/lib/glucose-get-last.js
@@ -14,7 +14,8 @@ var getLastGlucose = function (data) {
 
     //console.error(now.glucose);
     for (i=1; i < data.length; i++) {
-        if (typeof data[i] !== 'undefined' && data[i].glucose > 38) {
+        // only use data from the same device as the most recent BG data point
+        if (typeof data[i] !== 'undefined' && data[i].glucose > 38 && data[i].device == now.device) {
             var then = data[i];
             var then_date = then.date || Date.parse(then.display_time) || Date.parse(then.dateString);
             var avgdelta = 0;
only use data from the same device as the most recent BG data point