App Crashes in between while executing test cases

[ritesh2689]

Appium Version - 1.12.0
iOS version - iPhone 6s - 12.1 , iPhone 6 - 11.4 (Real Device)
macOS version - 10.14.4
Appium Java Client - 6.1.0
Xcode version - 10.2.1
node version - 10.15.3
npm version - 6.9.0

Above is the environment i am using. But at times app crashes with below logs.

2019-05-03 10:24:32:983 - [WD Proxy] Got an unexpected response: {"value":"The application under test with bundle id '<bundle_id>' is not running, possibly crashed","sessionId":"A53231FF-183D-49BD-9063-52644A2E414B","status":889}

Can someone please help to figure out the root cause. The issue is just intermittent and does not happen always. I am seeing above issue while calling launchApp method as below:-

    Map<String, Object> params = new HashMap<>();
    params.put("bundleId", jsonObjectUtil.getObject("bundleId"));
    JavascriptExecutor javascriptExecutor = (JavascriptExecutor) driver;
    javascriptExecutor.executeScript("mobile: launchApp", params);

[ritesh2689]

can someone update on this